Serve mojo WebUI resources from the same origin as the WebUI itself.

content/browser/webui/web_ui_mojo_browsertest.cc

 // Copyright 2014 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 <limits>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
+#include "base/path_service.h"
 #include "base/run_loop.h"
 #include "base/strings/string_util.h"
 #include "content/browser/webui/web_ui_controller_factory_registry.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_ui_controller.h"
 #include "content/public/browser/web_ui_data_source.h"
@@ skipping 25 matching lines @@
   if (id == mojo::kBindingsModuleName ||
       id == mojo::kBufferModuleName ||
       id == mojo::kCodecModuleName ||
       id == mojo::kConnectionModuleName ||
       id == mojo::kConnectorModuleName ||
       id == mojo::kUnicodeModuleName ||
       id == mojo::kRouterModuleName ||
       id == mojo::kValidatorModuleName)
     return false;
 
+  if (id.find(".mojom") != std::string::npos) {
+    std::string contents;
+    CHECK(base::ReadFileToString(mojo::test::GetFilePathForJSResource(id),
+                                 &contents, std::string::npos))
+        << id;
+    base::RefCountedString* ref_contents = new base::RefCountedString;
+    ref_contents->data() = contents;
+    callback.Run(ref_contents);
+    return true;
+  }
+
+  base::FilePath path;
+  DCHECK(base::PathService::Get(content::DIR_TEST_DATA, &path));
+  path = path.AppendASCII(id.substr(0, id.find("?")));
   std::string contents;
-  CHECK(base::ReadFileToString(mojo::test::GetFilePathForJSResource(id),
-                               &contents,
-                               std::string::npos)) << id;
+  CHECK(base::ReadFileToString(path, &contents, std::string::npos)) << id;

[magjed_chromium, 2015/11/24 08:55:50]

After your CL, we are hitting this CHECK on the Cast Linux bot,
content_browsertests, with the following failing tests:
WebUIMojoTest.EndToEndPing and WebUIMojoTest.ConnectToApplication.
https://build.chromium.org/p/chromium.linux/builders/Cast%20Linux/builds/1315...

   base::RefCountedString* ref_contents = new base::RefCountedString;
   ref_contents->data() = contents;
   callback.Run(ref_contents);
   return true;
 }
 
 class BrowserTargetImpl : public BrowserTarget {
  public:
   BrowserTargetImpl(base::RunLoop* run_loop,
                     mojo::InterfaceRequest<BrowserTarget> request)
@@ skipping 14 matching lines @@
   base::RunLoop* run_loop_;
 
  private:
   mojo::Binding<BrowserTarget> binding_;
   DISALLOW_COPY_AND_ASSIGN(BrowserTargetImpl);
 };
 
 // WebUIController that sets up mojo bindings.
 class TestWebUIController : public WebUIController {
  public:
-   TestWebUIController(WebUI* web_ui, base::RunLoop* run_loop)
-      : WebUIController(web_ui),
-        run_loop_(run_loop) {
+  TestWebUIController(WebUI* web_ui, base::RunLoop* run_loop)
+      : WebUIController(web_ui), run_loop_(run_loop) {
     content::WebUIDataSource* data_source =
-        WebUIDataSource::AddMojoDataSource(
-            web_ui->GetWebContents()->GetBrowserContext());
+        WebUIDataSource::Create("mojo-web-ui");
+    data_source->AddMojoResources();
     data_source->SetRequestFilter(base::Bind(&GetResource));
+    content::WebUIDataSource::Add(web_ui->GetWebContents()->GetBrowserContext(),
+                                  data_source);
   }
 
  protected:
   base::RunLoop* run_loop_;
   scoped_ptr<BrowserTargetImpl> browser_target_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TestWebUIController);
 };
 
@@ skipping 88 matching lines @@
 // it from the browser to the page and back.
 IN_PROC_BROWSER_TEST_F(WebUIMojoTest, EndToEndPing) {
   if (!IsGeneratedResourceAvailable(
           "content/test/data/web_ui_test_mojo_bindings.mojom"))
     return;
 
   got_message = false;
   ASSERT_TRUE(embedded_test_server()->Start());
   base::RunLoop run_loop;
   factory()->set_run_loop(&run_loop);
-  GURL test_url(embedded_test_server()->GetURL("/web_ui_mojo.html?ping"));
+  GURL test_url("chrome://mojo-web-ui/web_ui_mojo.html?ping");
   NavigateToURL(shell(), test_url);
   // RunLoop is quit when message received from page.
   run_loop.Run();
   EXPECT_TRUE(got_message);
 
   // Check that a second render frame in the same renderer process works
   // correctly.
   Shell* other_shell = CreateBrowser();
   got_message = false;
   base::RunLoop other_run_loop;
   factory()->set_run_loop(&other_run_loop);
   NavigateToURL(other_shell, test_url);
   // RunLoop is quit when message received from page.
   other_run_loop.Run();
   EXPECT_TRUE(got_message);
   EXPECT_EQ(shell()->web_contents()->GetRenderProcessHost(),
             other_shell->web_contents()->GetRenderProcessHost());
 }
 
 // Loads a webui page that connects to a test Mojo application via the browser's
 // Mojo shell interface.
 IN_PROC_BROWSER_TEST_F(WebUIMojoTest, ConnectToApplication) {
   if (!IsGeneratedResourceAvailable(
           "content/public/test/test_mojo_service.mojom"))
     return;
 
   ASSERT_TRUE(embedded_test_server()->Start());
   NavigateToURL(shell(),
-                embedded_test_server()->GetURL("/web_ui_mojo_shell_test.html"));
+                GURL("chrome://mojo-web-ui/web_ui_mojo_shell_test.html"));
 
   DOMMessageQueue message_queue;
   std::string message;
   ASSERT_TRUE(message_queue.WaitForMessage(&message));
   EXPECT_EQ("true", message);
 }
 
 }  // namespace
 }  // namespace content