Use mojo for Chrome Loading, Part 1

content/browser/loader/mojo_async_resource_handler_unittest.cc

Index: content/browser/loader/mojo_async_resource_handler_unittest.cc
diff --git a/content/browser/loader/mojo_async_resource_handler_unittest.cc b/content/browser/loader/mojo_async_resource_handler_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3a642422253cf001c1967d012fba195ce0729268
--- /dev/null
+++ b/content/browser/loader/mojo_async_resource_handler_unittest.cc
@@ -0,0 +1,1151 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/loader/mojo_async_resource_handler.h"
+
+#include <string.h>
+
+#include <utility>
+
+#include "base/bind.h"
+#include "base/callback.h"
+#include "base/files/file_path.h"
+#include "base/memory/ptr_util.h"
+#include "base/memory/scoped_vector.h"
+#include "base/memory/weak_ptr.h"
+#include "base/run_loop.h"
+#include "content/browser/loader/resource_dispatcher_host_impl.h"
+#include "content/browser/loader/resource_request_info_impl.h"
+#include "content/browser/loader/test_url_loader_client.h"
+#include "content/common/resource_request_completion_status.h"
+#include "content/common/url_loader.mojom.h"
+#include "content/public/browser/appcache_service.h"
+#include "content/public/browser/navigation_data.h"
+#include "content/public/browser/resource_context.h"
+#include "content/public/browser/resource_controller.h"
+#include "content/public/browser/resource_dispatcher_host_delegate.h"
+#include "content/public/browser/resource_throttle.h"
+#include "content/public/browser/stream_info.h"
+#include "content/public/common/resource_response.h"
+#include "content/public/common/resource_type.h"
+#include "content/public/test/test_browser_context.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "mojo/public/c/system/data_pipe.h"
+#include "mojo/public/c/system/types.h"
+#include "mojo/public/cpp/system/data_pipe.h"
+#include "net/base/auth.h"
+#include "net/base/net_errors.h"
+#include "net/http/http_response_headers.h"
+#include "net/http/http_response_info.h"
+#include "net/http/http_status_code.h"
+#include "net/http/http_util.h"
+#include "net/ssl/client_cert_store.h"
+#include "net/test/url_request/url_request_failed_job.h"
+#include "net/url_request/url_request.h"
+#include "net/url_request/url_request_context.h"
+#include "net/url_request/url_request_filter.h"
+#include "net/url_request/url_request_status.h"
+#include "net/url_request/url_request_test_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/base/page_transition_types.h"
+
+namespace content {
+namespace {
+
+constexpr int kSizeMimeSnifferRequiresForFirstOnWillRead = 2048;
+
+class TestResourceDispatcherHostDelegate final
+    : public ResourceDispatcherHostDelegate {
+ public:
+  TestResourceDispatcherHostDelegate() = default;
+  ~TestResourceDispatcherHostDelegate() override {
+    EXPECT_EQ(num_on_response_started_calls_expectation_,
+              num_on_response_started_calls_);
+  }
+
+  bool ShouldBeginRequest(const std::string& method,
+                          const GURL& url,
+                          ResourceType resource_type,
+                          ResourceContext* resource_context) override {
+    ADD_FAILURE() << "ShouldBeginRequest should not be called.";
+    return false;
+  }
+
+  void RequestBeginning(net::URLRequest* request,
+                        ResourceContext* resource_context,
+                        AppCacheService* appcache_service,
+                        ResourceType resource_type,
+                        ScopedVector<ResourceThrottle>* throttles) override {
+    ADD_FAILURE() << "RequestBeginning should not be called.";
+  }
+
+  void DownloadStarting(net::URLRequest* request,
+                        ResourceContext* resource_context,
+                        int child_id,
+                        int route_id,
+                        bool is_content_initiated,
+                        bool must_download,
+                        ScopedVector<ResourceThrottle>* throttles) override {
+    ADD_FAILURE() << "DownloadStarting should not be called.";
+  }
+
+  ResourceDispatcherHostLoginDelegate* CreateLoginDelegate(
+      net::AuthChallengeInfo* auth_info,
+      net::URLRequest* request) override {
+    ADD_FAILURE() << "CreateLoginDelegate should not be called.";
+    return nullptr;
+  }
+
+  bool HandleExternalProtocol(
+      const GURL& url,
+      int child_id,
+      const ResourceRequestInfo::WebContentsGetter& web_contents_getter,
+      bool is_main_frame,
+      ui::PageTransition page_transition,
+      bool has_user_gesture,
+      ResourceContext* resource_context) override {
+    ADD_FAILURE() << "HandleExternalProtocol should not be called.";
+    return false;
+  }
+
+  bool ShouldForceDownloadResource(const GURL& url,
+                                   const std::string& mime_type) override {
+    ADD_FAILURE() << "ShouldForceDownloadResource should not be called.";
+    return false;
+  }
+
+  bool ShouldInterceptResourceAsStream(net::URLRequest* request,
+                                       const base::FilePath& plugin_path,
+                                       const std::string& mime_type,
+                                       GURL* origin,
+                                       std::string* payload) override {
+    ADD_FAILURE() << "ShouldInterceptResourceAsStream should not be called.";
+    return false;
+  }
+
+  void OnStreamCreated(net::URLRequest* request,
+                       std::unique_ptr<content::StreamInfo> stream) override {
+    ADD_FAILURE() << "OnStreamCreated should not be called.";
+  }
+
+  void OnResponseStarted(net::URLRequest* request,
+                         ResourceContext* resource_context,
+                         ResourceResponse* response) override {
+    ++num_on_response_started_calls_;
+  }
+
+  void OnRequestRedirected(const GURL& redirect_url,
+                           net::URLRequest* request,
+                           ResourceContext* resource_context,
+                           ResourceResponse* response) override {
+    ADD_FAILURE() << "OnRequestRedirected should not be called.";
+  }
+
+  void RequestComplete(net::URLRequest* url_request) override {
+    ADD_FAILURE() << "RequestComplete should not be called.";
+  }
+
+  bool ShouldEnableLoFiMode(
+      const net::URLRequest& url_request,
+      content::ResourceContext* resource_context) override {
+    ADD_FAILURE() << "ShouldEnableLoFiMode should not be called.";
+    return false;
+  }
+
+  NavigationData* GetNavigationData(net::URLRequest* request) const override {
+    ADD_FAILURE() << "GetNavigationData should not be called.";
+    return nullptr;
+  }
+
+  std::unique_ptr<net::ClientCertStore> CreateClientCertStore(
+      ResourceContext* resource_context) override {
+    ADD_FAILURE() << "CreateClientCertStore should not be called.";
+    return nullptr;
+  }
+
+  int num_on_response_started_calls() const {
+    return num_on_response_started_calls_;
+  }
+  void set_num_on_response_started_calls_expectation(int expectation) {
+    num_on_response_started_calls_expectation_ = expectation;
+  }
+
+ private:
+  int num_on_response_started_calls_ = 0;
+  int num_on_response_started_calls_expectation_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(TestResourceDispatcherHostDelegate);
+};
+
+class TestResourceController : public ResourceController {
+ public:
+  TestResourceController() {}
+  ~TestResourceController() override {}
+
+  void Cancel() override { ADD_FAILURE() << "Cancel should not be called."; }
+
+  void CancelAndIgnore() override {
+    ADD_FAILURE() << "CancelAndIgnore should not be called.";
+  }
+
+  void CancelWithError(int error_code) override {
+    is_cancel_with_error_called_ = true;
+    error_ = error_code;
+    if (quit_closure_)
+      quit_closure_.Run();
+  }
+
+  void Resume() override { ++num_resume_calls_; }
+
+  void RunUntilCancelWithErrorCalled() {
+    base::RunLoop run_loop;
+    quit_closure_ = run_loop.QuitClosure();
+    run_loop.Run();
+  }
+
+  void set_quit_closure(const base::Closure& quit_closure) {
+    quit_closure_ = quit_closure;
+  }
+
+  bool is_cancel_with_error_called() const {
+    return is_cancel_with_error_called_;
+  }
+  int error() const { return error_; }
+  int num_resume_calls() const { return num_resume_calls_; }
+
+ private:
+  bool is_cancel_with_error_called_ = false;
+  int error_ = net::OK;
+  int num_resume_calls_ = 0;
+  base::Closure quit_closure_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestResourceController);
+};
+
+class MojoAsyncResourceHandlerWithCustomDataPipeOperations
+    : public MojoAsyncResourceHandler {
+ public:
+  MojoAsyncResourceHandlerWithCustomDataPipeOperations(
+      net::URLRequest* request,
+      ResourceDispatcherHostImpl* rdh,
+      mojo::InterfaceRequest<mojom::URLLoader> mojo_request,
+      mojom::URLLoaderClientPtr url_loader_client)
+      : MojoAsyncResourceHandler(request,
+                                 rdh,
+                                 std::move(mojo_request),
+                                 std::move(url_loader_client)) {}
+  ~MojoAsyncResourceHandlerWithCustomDataPipeOperations() override {}
+
+  void ResetBeginWriteExpectation() { is_begin_write_expectation_set_ = false; }
+
+  void set_begin_write_expectation(MojoResult begin_write_expectation) {
+    is_begin_write_expectation_set_ = true;
+    begin_write_expectation_ = begin_write_expectation;
+  }
+  void set_end_write_expectation(MojoResult end_write_expectation) {
+    is_end_write_expectation_set_ = true;
+    end_write_expectation_ = end_write_expectation;
+  }
+
+ private:
+  MojoResult BeginWrite(void** data, uint32_t* available) override {
+    if (is_begin_write_expectation_set_)
+      return begin_write_expectation_;
+    return MojoAsyncResourceHandler::BeginWrite(data, available);
+  }
+  MojoResult EndWrite(uint32_t written) override {
+    if (is_end_write_expectation_set_)
+      return end_write_expectation_;
+    return MojoAsyncResourceHandler::EndWrite(written);
+  }
+
+  bool is_begin_write_expectation_set_ = false;
+  bool is_end_write_expectation_set_ = false;
+  MojoResult begin_write_expectation_ = MOJO_RESULT_UNKNOWN;
+  MojoResult end_write_expectation_ = MOJO_RESULT_UNKNOWN;
+
+  DISALLOW_COPY_AND_ASSIGN(
+      MojoAsyncResourceHandlerWithCustomDataPipeOperations);
+};
+
+class MojoAsyncResourceHandlerTestBase {
+ public:
+  MojoAsyncResourceHandlerTestBase()
+      : thread_bundle_(TestBrowserThreadBundle::IO_MAINLOOP),
+        browser_context_(new TestBrowserContext()) {
+    MojoAsyncResourceHandler::SetAllocationSizeForTesting(32 * 1024);
+    rdh_.SetDelegate(&rdh_delegate_);
+
+    url_request_delegate_.reset(new net::TestDelegate());
+    net::URLRequestContext* request_context =
+        browser_context_->GetResourceContext()->GetRequestContext();
+    request_ = request_context->CreateRequest(
+        net::URLRequestFailedJob::GetMockHttpUrl(net::ERR_TIMED_OUT),
+        net::DEFAULT_PRIORITY, url_request_delegate_.get());
+    ResourceRequestInfo::AllocateForTesting(
+        request_.get(),                          // request
+        RESOURCE_TYPE_XHR,                       // resource_type
+        browser_context_->GetResourceContext(),  // context
+        2,                                       // render_process_id
+        0,                                       // render_view_id
+        0,                                       // render_frame_id
+        true,                                    // is_main_frame
+        false,                                   // parent_is_main_frame
+        false,                                   // allow_download
+        true,                                    // is_async
+        false                                    // is_using_lofi
+        );
+    handler_.reset(new MojoAsyncResourceHandlerWithCustomDataPipeOperations(
+        request_.get(), &rdh_, nullptr,
+        url_loader_client_.CreateInterfacePtrAndBind()));
+    handler_->SetController(&resource_controller_);
+  }
+
+  virtual ~MojoAsyncResourceHandlerTestBase() {
+    net::URLRequestFilter::GetInstance()->ClearHandlers();
+    MojoAsyncResourceHandler::SetAllocationSizeForTesting(
+        MojoAsyncResourceHandler::kDefaultAllocationSize);
+    base::RunLoop().RunUntilIdle();
+  }
+
+  // Returns false if something bad happens.
+  bool CallOnWillStart() {
+    bool defer = false;
+    if (!handler_->OnWillStart(request_->url(), &defer)) {
+      ADD_FAILURE() << "OnWillStart returns false.";
+      return false;
+    }
+    if (defer) {
+      ADD_FAILURE() << "OnWillStart sets |defer| true.";
+      return false;
+    }
+    return true;
+  }
+
+  // Returns false if something bad happens.
+  bool CallOnWillStartAndOnResponseStarted() {
+    rdh_delegate_.set_num_on_response_started_calls_expectation(1);
+    if (!CallOnWillStart())
+      return false;
+
+    scoped_refptr<ResourceResponse> response = new ResourceResponse();
+    bool defer = false;
+    if (!handler_->OnResponseStarted(response.get(), &defer)) {
+      ADD_FAILURE() << "OnResponseStarted returns false.";
+      return false;
+    }
+    if (defer) {
+      ADD_FAILURE() << "OnResponseStarted sets |defer| true.";
+      return false;
+    }
+    if (url_loader_client_.has_received_response()) {
+      ADD_FAILURE() << "URLLoaderClient unexpectedly gets a response.";
+      return false;
+    }
+    url_loader_client_.RunUntilResponseReceived();
+    return true;
+  }
+
+  TestBrowserThreadBundle thread_bundle_;
+  TestResourceDispatcherHostDelegate rdh_delegate_;
+  ResourceDispatcherHostImpl rdh_;
+  TestURLLoaderClient url_loader_client_;
+  TestResourceController resource_controller_;
+  std::unique_ptr<TestBrowserContext> browser_context_;
+  std::unique_ptr<net::TestDelegate> url_request_delegate_;
+  std::unique_ptr<net::URLRequest> request_;
+  std::unique_ptr<MojoAsyncResourceHandlerWithCustomDataPipeOperations>
+      handler_;
+
+  DISALLOW_COPY_AND_ASSIGN(MojoAsyncResourceHandlerTestBase);
+};
+
+class MojoAsyncResourceHandlerTest : public MojoAsyncResourceHandlerTestBase,
+                                     public ::testing::Test {};
+
+// This test class is parameterized with MojoAsyncResourceHandler's allocation
+// size.
+class MojoAsyncResourceHandlerWithAllocationSizeTest
+    : public MojoAsyncResourceHandlerTestBase,
+      public ::testing::TestWithParam<size_t> {
+ protected:
+  MojoAsyncResourceHandlerWithAllocationSizeTest() {
+    MojoAsyncResourceHandler::SetAllocationSizeForTesting(GetParam());
+  }
+};
+
+TEST_F(MojoAsyncResourceHandlerTest, InFlightRequests) {
+  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
+  handler_ = nullptr;
+  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnWillStart) {
+  bool defer = false;
+  EXPECT_TRUE(handler_->OnWillStart(request_->url(), &defer));
+  EXPECT_FALSE(defer);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnResponseStarted) {
+  rdh_delegate_.set_num_on_response_started_calls_expectation(1);
+  ASSERT_TRUE(CallOnWillStart());
+
+  scoped_refptr<ResourceResponse> response = new ResourceResponse();
+  response->head.content_length = 99;
+  response->head.request_start =
+      base::TimeTicks::UnixEpoch() + base::TimeDelta::FromDays(14);
+  response->head.response_start =
+      base::TimeTicks::UnixEpoch() + base::TimeDelta::FromDays(28);
+
+  bool defer = false;
+
+  EXPECT_EQ(0, rdh_delegate_.num_on_response_started_calls());
+  base::TimeTicks now1 = base::TimeTicks::Now();
+  ASSERT_TRUE(handler_->OnResponseStarted(response.get(), &defer));
+  base::TimeTicks now2 = base::TimeTicks::Now();
+
+  EXPECT_FALSE(defer);
+  EXPECT_EQ(request_->creation_time(), response->head.request_start);
+  EXPECT_LE(now1, response->head.response_start);
+  EXPECT_LE(response->head.response_start, now2);
+  EXPECT_EQ(1, rdh_delegate_.num_on_response_started_calls());
+
+  url_loader_client_.RunUntilResponseReceived();
+  EXPECT_EQ(response->head.request_start,
+            url_loader_client_.response_head().request_start);
+  EXPECT_EQ(response->head.response_start,
+            url_loader_client_.response_head().response_start);
+  EXPECT_EQ(99, url_loader_client_.response_head().content_length);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnWillReadAndInFlightRequests) {
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  EXPECT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  EXPECT_EQ(1, rdh_.num_in_flight_requests_for_testing());
+  handler_ = nullptr;
+  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnWillReadWithInsufficientResource) {
+  rdh_.set_max_num_in_flight_requests_per_process(0);
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  EXPECT_FALSE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  EXPECT_FALSE(io_buffer);
+  EXPECT_EQ(0, io_buffer_size);
+  EXPECT_EQ(1, rdh_.num_in_flight_requests_for_testing());
+  EXPECT_TRUE(resource_controller_.is_cancel_with_error_called());
+  EXPECT_EQ(net::ERR_INSUFFICIENT_RESOURCES, resource_controller_.error());
+  handler_ = nullptr;
+  EXPECT_EQ(0, rdh_.num_in_flight_requests_for_testing());
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnWillReadAndOnReadCompleted) {
+  bool defer = false;
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(io_buffer);
+  // The buffer size that the mime sniffer requires implicitly.
+  ASSERT_GE(io_buffer_size, kSizeMimeSnifferRequiresForFirstOnWillRead);
+
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  io_buffer->data()[0] = 'A';
+  io_buffer->data()[1] = 'B';
+  ASSERT_TRUE(handler_->OnReadCompleted(2, &defer));
+  EXPECT_FALSE(defer);
+
+  std::string contents;
+  while (contents.size() < 2) {
+    char buffer[16];
+    uint32_t read_size = sizeof(buffer);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
+                          &read_size, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_SHOULD_WAIT) {
+      base::RunLoop().RunUntilIdle();
+      continue;
+    }
+    contents.append(buffer, read_size);
+  }
+  EXPECT_EQ("AB", contents);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest,
+       OnWillReadAndOnReadCompletedWithInsufficientInitialCapacity) {
+  MojoAsyncResourceHandler::SetAllocationSizeForTesting(2);
+
+  bool defer = false;
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(io_buffer);
+  // The buffer size that the mime sniffer requires implicitly.
+  ASSERT_GE(io_buffer_size, kSizeMimeSnifferRequiresForFirstOnWillRead);
+
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  const std::string data("abcdefgh");
+  strcpy(io_buffer->data(), data.c_str());
+  ASSERT_TRUE(handler_->OnReadCompleted(data.size(), &defer));
+  EXPECT_TRUE(defer);
+
+  std::string contents;
+  while (contents.size() < data.size()) {
+    // This is needed for Resume to be called.
+    base::RunLoop().RunUntilIdle();
+    char buffer[16];
+    uint32_t read_size = sizeof(buffer);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
+                          &read_size, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_SHOULD_WAIT)
+      continue;
+    ASSERT_EQ(MOJO_RESULT_OK, result);
+    contents.append(buffer, read_size);
+  }
+  EXPECT_EQ(data, contents);
+  EXPECT_EQ(0, resource_controller_.num_resume_calls());
+}
+
+TEST_F(MojoAsyncResourceHandlerTest,
+       IOBufferFromOnWillReadShouldRemainValidEvenIfHandlerIsGone) {
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(io_buffer);
+  // The io_buffer size that the mime sniffer requires implicitly.
+  ASSERT_GE(io_buffer_size, kSizeMimeSnifferRequiresForFirstOnWillRead);
+
+  handler_ = nullptr;
+  url_loader_client_.Unbind();
+  base::RunLoop().RunUntilIdle();
+
+  // Hopefully ASAN checks this operation's validity.
+  io_buffer->data()[0] = 'A';
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnResponseCompleted) {
+  bool defer = false;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+
+  ResourceRequestInfoImpl::ForRequest(request_.get())
+      ->set_was_ignored_by_handler(false);
+  net::URLRequestStatus status(net::URLRequestStatus::SUCCESS, net::OK);
+  std::string security_info = "info0";
+
+  base::TimeTicks now1 = base::TimeTicks::Now();
+  handler_->OnResponseCompleted(status, security_info, &defer);
+  base::TimeTicks now2 = base::TimeTicks::Now();
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::OK, url_loader_client_.completion_status().error_code);
+  EXPECT_FALSE(url_loader_client_.completion_status().was_ignored_by_handler);
+  EXPECT_EQ("info0", url_loader_client_.completion_status().security_info);
+  EXPECT_LE(now1, url_loader_client_.completion_status().completion_time);
+  EXPECT_LE(url_loader_client_.completion_status().completion_time, now2);
+  EXPECT_EQ(request_->GetTotalReceivedBytes(),
+            url_loader_client_.completion_status().encoded_data_length);
+}
+
+// This test case sets different status values from OnResponseCompleted.
+TEST_F(MojoAsyncResourceHandlerTest, OnResponseCompleted2) {
+  rdh_.SetDelegate(nullptr);
+  bool defer = false;
+  // Don't use CallOnWillStartAndOnResponseStarted as this test case manually
+  // sets the null delegate.
+  ASSERT_TRUE(CallOnWillStart());
+  scoped_refptr<ResourceResponse> response = new ResourceResponse();
+  ASSERT_TRUE(handler_->OnResponseStarted(response.get(), &defer));
+  ASSERT_FALSE(defer);
+  ASSERT_FALSE(url_loader_client_.has_received_response());
+  url_loader_client_.RunUntilResponseReceived();
+
+  ResourceRequestInfoImpl::ForRequest(request_.get())
+      ->set_was_ignored_by_handler(true);
+  net::URLRequestStatus status(net::URLRequestStatus::CANCELED,
+                               net::ERR_ABORTED);
+  std::string security_info = "info1";
+
+  base::TimeTicks now1 = base::TimeTicks::Now();
+  handler_->OnResponseCompleted(status, security_info, &defer);
+  base::TimeTicks now2 = base::TimeTicks::Now();
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::ERR_ABORTED,
+            url_loader_client_.completion_status().error_code);
+  EXPECT_TRUE(url_loader_client_.completion_status().was_ignored_by_handler);
+  EXPECT_EQ("info1", url_loader_client_.completion_status().security_info);
+  EXPECT_LE(now1, url_loader_client_.completion_status().completion_time);
+  EXPECT_LE(url_loader_client_.completion_status().completion_time, now2);
+  EXPECT_EQ(request_->GetTotalReceivedBytes(),
+            url_loader_client_.completion_status().encoded_data_length);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnResponseCompletedWithCanceledTimedOut) {
+  net::URLRequestStatus status(net::URLRequestStatus::CANCELED,
+                               net::ERR_TIMED_OUT);
+  bool defer = false;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  handler_->OnResponseCompleted(status, "security_info", &defer);
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::ERR_TIMED_OUT,
+            url_loader_client_.completion_status().error_code);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, OnResponseCompletedWithFailedTimedOut) {
+  net::URLRequestStatus status(net::URLRequestStatus::FAILED,
+                               net::ERR_TIMED_OUT);
+  bool defer = false;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  handler_->OnResponseCompleted(status, "security_info", &defer);
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::ERR_TIMED_OUT,
+            url_loader_client_.completion_status().error_code);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, ResponseCompletionShouldCloseDataPipe) {
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  bool defer = false;
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+  ASSERT_TRUE(handler_->OnReadCompleted(0, &defer));
+  EXPECT_FALSE(defer);
+
+  net::URLRequestStatus status(net::URLRequestStatus::SUCCESS, net::OK);
+  handler_->OnResponseCompleted(status, "security_info", &defer);
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::OK, url_loader_client_.completion_status().error_code);
+
+  // This is needed because |*io_buffer| may keep the data producer alive.
+  io_buffer = nullptr;
+
+  while (true) {
+    char buffer[16];
+    uint32_t read_size = sizeof(buffer);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
+                          &read_size, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_FAILED_PRECONDITION)
+      break;
+    ASSERT_EQ(result, MOJO_RESULT_SHOULD_WAIT);
+  }
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, ResponseErrorDuringBodyTransmission) {
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+  ASSERT_GT(io_buffer_size, 0);
+  memset(io_buffer->data(), 'a', io_buffer_size);
+  bool defer = false;
+  ASSERT_TRUE(handler_->OnReadCompleted(io_buffer_size, &defer));
+  // We don't care |defer|'s value here.
+
+  defer = false;
+  net::URLRequestStatus status(net::URLRequestStatus::FAILED, net::ERR_FAILED);
+  handler_->OnResponseCompleted(status, "security_info", &defer);
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::ERR_FAILED, url_loader_client_.completion_status().error_code);
+
+  // This is needed because |*io_buffer| may keep the data producer alive.
+  io_buffer = nullptr;
+
+  std::string actual;
+  while (true) {
+    char buf[16];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_FAILED_PRECONDITION)
+      break;
+    if (result == MOJO_RESULT_SHOULD_WAIT) {
+      base::RunLoop().RunUntilIdle();
+      continue;
+    }
+    EXPECT_EQ(MOJO_RESULT_OK, result);
+    actual.append(buf, read_size);
+  }
+  EXPECT_EQ(std::string(io_buffer_size, 'a'), actual);
+}
+
+// In this case, an error is notified after OnWillRead, before OnReadCompleted.
+TEST_F(MojoAsyncResourceHandlerTest, ResponseErrorDuringBodyTransmission2) {
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+  bool defer = false;
+  net::URLRequestStatus status(net::URLRequestStatus::FAILED, net::ERR_FAILED);
+  handler_->OnResponseCompleted(status, "security_info", &defer);
+  EXPECT_FALSE(defer);
+
+  url_loader_client_.RunUntilComplete();
+  EXPECT_TRUE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::ERR_FAILED, url_loader_client_.completion_status().error_code);
+
+  // This is needed because |*io_buffer| may keep the data producer alive.
+  io_buffer = nullptr;
+
+  while (true) {
+    char buf[16];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_FAILED_PRECONDITION)
+      break;
+    ASSERT_EQ(MOJO_RESULT_SHOULD_WAIT, result);
+    base::RunLoop().RunUntilIdle();
+  }
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, BeginWriteFailsOnWillRead) {
+  handler_->set_begin_write_expectation(MOJO_RESULT_UNKNOWN);
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_FALSE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  EXPECT_FALSE(resource_controller_.is_cancel_with_error_called());
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, BeginWriteReturnsShouldWaitOnWillRead) {
+  handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  EXPECT_TRUE(io_buffer);
+  EXPECT_GT(io_buffer_size, 0);
+}
+
+TEST_F(MojoAsyncResourceHandlerTest,
+       BeginWriteReturnsShouldWaitOnWillReadAndThenReturnsOK) {
+  handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  size_t written = 0;
+  while (true) {
+    scoped_refptr<net::IOBuffer> io_buffer;
+    int io_buffer_size = 0;
+    ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+    EXPECT_TRUE(io_buffer);
+    EXPECT_GT(io_buffer_size, 0);
+    memset(io_buffer->data(), 'X', io_buffer_size);
+    written += io_buffer_size;
+    bool defer = false;
+    ASSERT_TRUE(handler_->OnReadCompleted(io_buffer_size, &defer));
+    if (defer)
+      break;
+  }
+
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+  handler_->ResetBeginWriteExpectation();
+  handler_->ResumeForTesting();
+
+  std::string actual;
+  while (actual.size() < written) {
+    char buf[16];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    ASSERT_TRUE(result == MOJO_RESULT_OK || result == MOJO_RESULT_SHOULD_WAIT);
+    if (result == MOJO_RESULT_OK)
+      actual.append(buf, read_size);
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_EQ(std::string(written, 'X'), actual);
+  EXPECT_EQ(1, resource_controller_.num_resume_calls());
+}
+
+TEST_F(MojoAsyncResourceHandlerTest,
+       EndWriteFailsOnWillReadWithInsufficientInitialCapacity) {
+  MojoAsyncResourceHandler::SetAllocationSizeForTesting(2);
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  handler_->set_end_write_expectation(MOJO_RESULT_UNKNOWN);
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  ASSERT_FALSE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+}
+
+TEST_F(MojoAsyncResourceHandlerTest, EndWriteFailsOnReadCompleted) {
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  bool defer = false;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+
+  handler_->set_end_write_expectation(MOJO_RESULT_SHOULD_WAIT);
+  ASSERT_FALSE(handler_->OnReadCompleted(io_buffer_size, &defer));
+}
+
+TEST_F(MojoAsyncResourceHandlerTest,
+       EndWriteFailsOnReadCompletedWithInsufficientInitialCapacity) {
+  MojoAsyncResourceHandler::SetAllocationSizeForTesting(2);
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  bool defer = false;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+
+  handler_->set_end_write_expectation(MOJO_RESULT_SHOULD_WAIT);
+  ASSERT_FALSE(handler_->OnReadCompleted(io_buffer_size, &defer));
+}
+
+TEST_F(MojoAsyncResourceHandlerTest,
+       EndWriteFailsOnResumeWithInsufficientInitialCapacity) {
+  MojoAsyncResourceHandler::SetAllocationSizeForTesting(8);
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  while (true) {
+    bool defer = false;
+    ASSERT_TRUE(handler_->OnReadCompleted(io_buffer_size, &defer));
+    ASSERT_GE(io_buffer_size, 0);
+    if (defer)
+      break;
+    ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  }
+
+  while (true) {
+    char buf[16];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_SHOULD_WAIT)
+      break;
+    ASSERT_EQ(MOJO_RESULT_OK, result);
+  }
+
+  handler_->set_end_write_expectation(MOJO_RESULT_SHOULD_WAIT);
+  resource_controller_.RunUntilCancelWithErrorCalled();
+  EXPECT_FALSE(url_loader_client_.has_received_completion());
+  EXPECT_TRUE(resource_controller_.is_cancel_with_error_called());
+  EXPECT_EQ(net::ERR_FAILED, resource_controller_.error());
+}
+
+TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
+       OnWillReadWithLongContents) {
+  bool defer = false;
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(io_buffer);
+  // The io_buffer size that the mime sniffer requires implicitly.
+  ASSERT_GE(io_buffer_size, kSizeMimeSnifferRequiresForFirstOnWillRead);
+  std::string expected;
+  for (int i = 0; i < 3 * io_buffer_size + 2; ++i)
+    expected += ('A' + i % 26);
+
+  ASSERT_TRUE(handler_->OnReadCompleted(0, &defer));
+  ASSERT_FALSE(defer);
+
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  size_t written = 0;
+  std::string actual;
+  while (actual.size() < expected.size()) {
+    while (written < expected.size() && !defer) {
+      ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+      const size_t to_be_written = std::min(static_cast<size_t>(io_buffer_size),
+                                            expected.size() - written);
+      memcpy(io_buffer->data(), &expected[written], to_be_written);
+      ASSERT_TRUE(handler_->OnReadCompleted(to_be_written, &defer));
+      written += to_be_written;
+    }
+
+    char buf[16];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    if (result != MOJO_RESULT_SHOULD_WAIT) {
+      ASSERT_EQ(MOJO_RESULT_OK, result);
+      actual.append(buf, read_size);
+    }
+    int resume_count = resource_controller_.num_resume_calls();
+    base::RunLoop().RunUntilIdle();
+    // Continue writing if controller->Resume() is called.
+    defer = (resume_count == resource_controller_.num_resume_calls());
+  }
+  EXPECT_EQ(expected, actual);
+}
+
+TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
+       BeginWriteFailsOnReadCompleted) {
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  bool defer = false;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+
+  handler_->set_begin_write_expectation(MOJO_RESULT_UNKNOWN);
+  ASSERT_FALSE(handler_->OnReadCompleted(io_buffer_size, &defer));
+}
+
+TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
+       BeginWriteReturnsShouldWaitOnReadCompleted) {
+  scoped_refptr<net::IOBuffer> io_buffer;
+  int io_buffer_size = 0;
+  bool defer = false;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+
+  handler_->set_begin_write_expectation(MOJO_RESULT_SHOULD_WAIT);
+  ASSERT_TRUE(handler_->OnReadCompleted(io_buffer_size, &defer));
+  EXPECT_TRUE(defer);
+}
+
+TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
+       BeginWriteFailsOnResume) {
+  bool defer = false;
+  int io_buffer_size = 0;
+  scoped_refptr<net::IOBuffer> io_buffer;
+
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(handler_->OnReadCompleted(0, &defer));
+  ASSERT_FALSE(defer);
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  while (!defer) {
+    ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+    ASSERT_TRUE(handler_->OnReadCompleted(io_buffer_size, &defer));
+  }
+  handler_->set_begin_write_expectation(MOJO_RESULT_UNKNOWN);
+
+  while (!resource_controller_.is_cancel_with_error_called()) {
+    char buf[256];
+    uint32_t read_size = sizeof(buf);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buf, &read_size,
+                          MOJO_READ_DATA_FLAG_NONE);
+    ASSERT_TRUE(result == MOJO_RESULT_OK || result == MOJO_RESULT_SHOULD_WAIT);
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_FALSE(url_loader_client_.has_received_completion());
+  EXPECT_EQ(net::ERR_FAILED, resource_controller_.error());
+  EXPECT_EQ(0, resource_controller_.num_resume_calls());
+}
+
+TEST_P(MojoAsyncResourceHandlerWithAllocationSizeTest, CancelWhileWaiting) {
+  bool defer = false;
+  ASSERT_TRUE(CallOnWillStartAndOnResponseStarted());
+
+  while (!defer) {
+    scoped_refptr<net::IOBuffer> io_buffer;
+    int io_buffer_size = 0;
+    ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+    ASSERT_TRUE(handler_->OnReadCompleted(io_buffer_size, &defer));
+  }
+
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  defer = false;
+  net::URLRequestStatus status(net::URLRequestStatus::CANCELED,
+                               net::ERR_ABORTED);
+  handler_->OnResponseCompleted(status, "security_info", &defer);
+
+  ASSERT_FALSE(url_loader_client_.has_received_completion());
+  url_loader_client_.RunUntilComplete();
+  EXPECT_EQ(net::ERR_ABORTED,
+            url_loader_client_.completion_status().error_code);
+
+  while (true) {
+    char buffer[16];
+    uint32_t read_size = sizeof(buffer);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
+                          &read_size, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_FAILED_PRECONDITION)
+      break;
+    base::RunLoop().RunUntilIdle();
+    DCHECK(result == MOJO_RESULT_SHOULD_WAIT || result == MOJO_RESULT_OK);
+  }
+
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(0, resource_controller_.num_resume_calls());
+}
+
+// Typically ResourceHandler methods are called in this order.
+TEST_P(
+    MojoAsyncResourceHandlerWithAllocationSizeTest,
+    OnWillStartThenOnResponseStartedThenOnWillReadThenOnReadCompletedThenOnResponseCompleted) {
+  rdh_delegate_.set_num_on_response_started_calls_expectation(1);
+  bool defer = false;
+
+  ASSERT_TRUE(handler_->OnWillStart(request_->url(), &defer));
+  ASSERT_FALSE(defer);
+  scoped_refptr<ResourceResponse> response = new ResourceResponse();
+  ASSERT_TRUE(handler_->OnResponseStarted(response.get(), &defer));
+  ASSERT_FALSE(defer);
+
+  ASSERT_FALSE(url_loader_client_.has_received_response());
+  url_loader_client_.RunUntilResponseReceived();
+
+  int io_buffer_size = 0;
+  scoped_refptr<net::IOBuffer> io_buffer;
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(io_buffer);
+  ASSERT_GT(io_buffer_size, 0);
+  io_buffer->data()[0] = 'A';
+
+  ASSERT_FALSE(url_loader_client_.response_body().is_valid());
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  ASSERT_TRUE(handler_->OnReadCompleted(1, &defer));
+  ASSERT_FALSE(defer);
+  net::URLRequestStatus status(net::URLRequestStatus::SUCCESS, net::OK);
+  handler_->OnResponseCompleted(status, "security info", &defer);
+  ASSERT_FALSE(defer);
+
+  ASSERT_FALSE(url_loader_client_.has_received_completion());
+  url_loader_client_.RunUntilComplete();
+  EXPECT_EQ(net::OK, url_loader_client_.completion_status().error_code);
+
+  // This is needed because |*io_buffer| may keep the data producer alive.
+  io_buffer = nullptr;
+
+  std::string body;
+  while (true) {
+    char buffer[16];
+    uint32_t read_size = sizeof(buffer);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
+                          &read_size, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_FAILED_PRECONDITION)
+      break;
+    if (result == MOJO_RESULT_SHOULD_WAIT) {
+      base::RunLoop().RunUntilIdle();
+    } else {
+      ASSERT_EQ(result, MOJO_RESULT_OK);
+      body.append(buffer, read_size);
+    }
+  }
+  EXPECT_EQ("A", body);
+}
+
+// MimeResourceHandler calls delegated ResourceHandler's methods in this order.
+TEST_P(
+    MojoAsyncResourceHandlerWithAllocationSizeTest,
+    OnWillStartThenOnWillReadThenOnResponseStartedThenOnReadCompletedThenOnResponseCompleted) {
+  rdh_delegate_.set_num_on_response_started_calls_expectation(1);
+  bool defer = false;
+
+  ASSERT_TRUE(handler_->OnWillStart(request_->url(), &defer));
+  ASSERT_FALSE(defer);
+
+  int io_buffer_size = 0;
+  scoped_refptr<net::IOBuffer> io_buffer;
+  ASSERT_TRUE(handler_->OnWillRead(&io_buffer, &io_buffer_size, -1));
+  ASSERT_TRUE(io_buffer);
+  ASSERT_GT(io_buffer_size, 0);
+  io_buffer->data()[0] = 'B';
+
+  ASSERT_FALSE(url_loader_client_.response_body().is_valid());
+  url_loader_client_.RunUntilResponseBodyArrived();
+  ASSERT_TRUE(url_loader_client_.response_body().is_valid());
+
+  scoped_refptr<ResourceResponse> response = new ResourceResponse();
+  ASSERT_TRUE(handler_->OnResponseStarted(response.get(), &defer));
+  ASSERT_FALSE(defer);
+
+  ASSERT_FALSE(url_loader_client_.has_received_response());
+  url_loader_client_.RunUntilResponseReceived();
+
+  ASSERT_TRUE(handler_->OnReadCompleted(1, &defer));
+  ASSERT_FALSE(defer);
+  net::URLRequestStatus status(net::URLRequestStatus::SUCCESS, net::OK);
+  handler_->OnResponseCompleted(status, "security info", &defer);
+  ASSERT_FALSE(defer);
+
+  ASSERT_FALSE(url_loader_client_.has_received_completion());
+  url_loader_client_.RunUntilComplete();
+  EXPECT_EQ(net::OK, url_loader_client_.completion_status().error_code);
+
+  // This is needed because |*io_buffer| may keep the data producer alive.
+  io_buffer = nullptr;
+
+  std::string body;
+  while (true) {
+    char buffer[16];
+    uint32_t read_size = sizeof(buffer);
+    MojoResult result =
+        mojo::ReadDataRaw(url_loader_client_.response_body(), buffer,
+                          &read_size, MOJO_READ_DATA_FLAG_NONE);
+    if (result == MOJO_RESULT_FAILED_PRECONDITION)
+      break;
+    if (result == MOJO_RESULT_SHOULD_WAIT) {
+      base::RunLoop().RunUntilIdle();
+    } else {
+      ASSERT_EQ(result, MOJO_RESULT_OK);
+      body.append(buffer, read_size);
+    }
+  }
+  EXPECT_EQ("B", body);
+}
+
+INSTANTIATE_TEST_CASE_P(MojoAsyncResourceHandlerWithAllocationSizeTest,
+                        MojoAsyncResourceHandlerWithAllocationSizeTest,
+                        ::testing::Values(8, 32 * 2014));
+}  // namespace
+}  // namespace content