Use modified URLRequest::Read() and delegate methods in components/

components/certificate_transparency/log_proof_fetcher.cc

Index: components/certificate_transparency/log_proof_fetcher.cc
diff --git a/components/certificate_transparency/log_proof_fetcher.cc b/components/certificate_transparency/log_proof_fetcher.cc
index 53c2e7c73398e654918e0fa06fa1fc9add0383d1..09a0438a8dee7b3bc07022a5fc58b8cf8430044e 100644
--- a/components/certificate_transparency/log_proof_fetcher.cc
+++ b/components/certificate_transparency/log_proof_fetcher.cc
@@ -47,7 +47,7 @@ class LogFetcher : public net::URLRequest::Delegate {
   ~LogFetcher() override {}
 
   // net::URLRequest::Delegate
-  void OnResponseStarted(net::URLRequest* request) override;
+  void OnResponseStarted(net::URLRequest* request, int net_error) override;
   void OnReadCompleted(net::URLRequest* request, int bytes_read) override;
 
   const std::string& assembled_response() const { return assembled_response_; }
@@ -102,12 +102,13 @@ LogFetcher::LogFetcher(net::URLRequestContext* request_context,
   url_request_->Start();
 }
 
-void LogFetcher::OnResponseStarted(net::URLRequest* request) {
+void LogFetcher::OnResponseStarted(net::URLRequest* request, int net_error) {
+  DCHECK_NE(net::ERR_IO_PENDING, net_error);
   DCHECK_EQ(url_request_.get(), request);
   int http_response_code = request->GetResponseCode();
 
-  if (!request->status().is_success()) {
-    InvokeFailureCallback(request->status().error(), http_response_code);
+  if (net_error != net::OK) {
+    InvokeFailureCallback(net_error, http_response_code);
     return;
   }
 
@@ -134,21 +135,9 @@ void LogFetcher::OnReadCompleted(net::URLRequest* request, int bytes_read) {
 }
 
 bool LogFetcher::HandleReadResult(int bytes_read) {
-  // Start by checking for an error condition.
-  // If there are errors, invoke the failure callback and clean up the
-  // request.
-  if (!url_request_->status().is_success() || bytes_read < 0) {
-    int net_error = url_request_->status().error();
-    if (net_error == net::OK)
-      net_error = net::URLRequestStatus::FAILED;
-
-    InvokeFailureCallback(net_error, net::HTTP_OK);
-    return false;
-  }
-
   // Not an error, but no data available, so wait for OnReadCompleted
   // callback.
-  if (url_request_->status().is_io_pending())
+  if (bytes_read == net::ERR_IO_PENDING)
     return false;
 
   // Nothing more to read from the stream - finish handling the response.
@@ -157,6 +146,15 @@ bool LogFetcher::HandleReadResult(int bytes_read) {
     return false;
   }
 
+  // Check for an error condition.

[Ryan Sleevi, 2016/09/07 18:48:08]

You can drop this line; it no longer grammatically fits with the rest of the
code (and probably shouldn't have been included on 137 to begin with)

+  // If there are errors, invoke the failure callback and clean up the
+  // request.
+  if (bytes_read < 0) {
+    int net_error = bytes_read;
+    InvokeFailureCallback(net_error, net::HTTP_OK);
+    return false;
+  }
+
   // Data is available, collect it and indicate another read is needed.
   DCHECK_GE(bytes_read, 0);
   // |bytes_read| is non-negative at this point, casting to size_t should be
@@ -177,9 +175,8 @@ bool LogFetcher::HandleReadResult(int bytes_read) {
 void LogFetcher::StartNextReadLoop() {
   bool continue_reading = true;
   while (continue_reading) {
-    int read_bytes = 0;
-    url_request_->Read(response_buffer_.get(), response_buffer_->size(),
-                       &read_bytes);
+    int read_bytes =
+        url_request_->Read(response_buffer_.get(), response_buffer_->size());
     continue_reading = HandleReadResult(read_bytes);
   }
 }