Use mojo for Chrome Loading, Part 1

content/browser/loader/resource_message_filter.cc

 // Copyright (c) 2012 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/resource_message_filter.h"
 
 #include "content/browser/appcache/chrome_appcache_service.h"
 #include "content/browser/fileapi/chrome_blob_storage_context.h"
 #include "content/browser/host_zoom_level_context.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
@@ skipping 46 matching lines @@
   return get_contexts_callback_.Run(resource_type, origin_pid, resource_context,
                                     request_context);
 }
 
 const HostZoomMap* ResourceMessageFilter::GetHostZoomMap() const {
   if (host_zoom_level_context_.get())
     return host_zoom_level_context_->GetHostZoomMap();
   return NULL;
 }
 
+bool ResourceMessageFilter::Send(IPC::Message* message) {
+  if (message->is_sync()) {
+    // We don't support sending synchronous messages from the browser.  If we
+    // really needed it, we can make this class derive from SyncMessageFilter
+    // but it seems better to not allow sending synchronous messages from the
+    // browser, since it might allow a corrupt/malicious renderer to hang us.

[jam, 2016/05/13 00:55:05]

no need for the second part of this comment, we don't send sync IPCs from the
browser period for the given reasons (there's an exception for android webview
but that's because it has to support existing android APIs).

[yhirano, 2016/05/17 12:38:49]

Done.

+    NOTREACHED() << "Can't send sync message through ResourceMessageFilter!";
+    return false;
+  }
+
+  if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
+    BrowserThread::PostTask(
+        BrowserThread::IO, FROM_HERE,
+        base::Bind(base::IgnoreResult(&ResourceMessageFilter::Send), this,
+                   message));
+    return true;
+  }
+
+  if (ResourceDispatcherHostImpl::Get()->SendWithMojoIfPossible(*message,
+                                                                this)) {
+    delete message;
+    return true;
+  }
+
+  return BrowserMessageFilter::Send(message);
+}
+
 base::WeakPtr<ResourceMessageFilter> ResourceMessageFilter::GetWeakPtr() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
   return weak_ptr_factory_.GetWeakPtr();
 }
 
 }  // namespace content