Migrate ResourceFetcher to use GC mojo wrappers.

No behavior change. This CL reduces potential risks of use-after-free bugs.

Bug: 1049056
Change-Id: Icb0a4d27b2bc6559642b1735dffcd4211d03190e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2136572Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Minoru Chikamune <chikamune@chromium.org>
Cr-Commit-Position: refs/heads/master@{#756595}

third_party/blink/renderer/platform/loader/fetch/DEPS

@@ -2,4 +2,5 @@ include_rules = [
   "+net/dns/public",
   "+services/network/public/cpp/fetch_api_utils.h",
   "+services/network/public/cpp/optional_trust_token_params.h",
+  "+third_party/blink/renderer/platform/mojo",
 ]

third_party/blink/renderer/platform/loader/fetch/resource_fetcher.cc

@@ -546,6 +546,7 @@ ResourceFetcher::ResourceFetcher(const ResourceFetcherInit& init)
           &ResourceFetcher::ResourceTimingReportTimerFired),
       frame_scheduler_(init.frame_scheduler ? init.frame_scheduler->GetWeakPtr()
                                             : nullptr),
+      blob_registry_remote_(nullptr),
       auto_load_images_(true),
       images_enabled_(true),
       allow_stale_resources_(false),
@@ -2113,7 +2114,7 @@ void ResourceFetcher::RevalidateStaleResource(Resource* stale_resource) {
 }
 
 mojom::blink::BlobRegistry* ResourceFetcher::GetBlobRegistry() {
-  if (!blob_registry_remote_) {
+  if (!blob_registry_remote_.is_bound()) {
     Platform::Current()->GetBrowserInterfaceBroker()->GetInterface(
         blob_registry_remote_.BindNewPipeAndPassReceiver(task_runner_));
   }
@@ -2141,6 +2142,7 @@ void ResourceFetcher::Trace(Visitor* visitor) {
   visitor->Trace(preloads_);
   visitor->Trace(matched_preloads_);
   visitor->Trace(resource_timing_info_map_);
+  visitor->Trace(blob_registry_remote_);
 }
 
 // static

third_party/blink/renderer/platform/loader/fetch/resource_fetcher.h

@@ -31,7 +31,6 @@
 #include <utility>
 
 #include "base/single_thread_task_runner.h"
-#include "mojo/public/cpp/bindings/remote.h"
 #include "third_party/blink/public/mojom/blob/blob_registry.mojom-blink.h"
 #include "third_party/blink/public/mojom/service_worker/controller_service_worker_mode.mojom-blink-forward.h"
 #include "third_party/blink/renderer/platform/heap/persistent.h"
@@ -39,6 +38,8 @@
 #include "third_party/blink/renderer/platform/loader/fetch/preload_key.h"
 #include "third_party/blink/renderer/platform/loader/fetch/resource_load_priority.h"
 #include "third_party/blink/renderer/platform/loader/fetch/resource_load_scheduler.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_remote.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_wrapper_mode.h"
 #include "third_party/blink/renderer/platform/platform_export.h"
 #include "third_party/blink/renderer/platform/timer.h"
 #include "third_party/blink/renderer/platform/wtf/hash_map.h"
@@ -420,7 +421,9 @@ class PLATFORM_EXPORT ResourceFetcher
 
   uint32_t inflight_keepalive_bytes_ = 0;
 
-  mojo::Remote<mojom::blink::BlobRegistry> blob_registry_remote_;
+  HeapMojoRemote<mojom::blink::BlobRegistry,
+                 HeapMojoWrapperMode::kWithoutContextObserver>
+      blob_registry_remote_;
 
   // This is not in the bit field below because we want to use AutoReset.
   bool is_in_request_resource_ = false;