Remove the concept of OutputSurface from ResourceProvider.

Pass around the compositor and worker context providers as needed
instead of grabbing them from ResourceProvider.

ResourceProvider is used by both the collator and the compositor
but only one of those will use OutputSurface eventually. This
allows easier use of ResourceProvider in test harnesses for now
also.

R=piman@chromium.org, reveman@chromium.org
BUG=311404, 606056
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review-Url: https://codereview.chromium.org/2007593005
Cr-Commit-Position: refs/heads/master@{#395769}

diff --git a/cc/raster/gpu_raster_buffer_provider.cc b/cc/raster/gpu_raster_buffer_provider.cc
index 51d8898..95bf983a 100644
--- a/cc/raster/gpu_raster_buffer_provider.cc
+++ b/cc/raster/gpu_raster_buffer_provider.cc

@@ -47,12 +47,9 @@
     TRACE_EVENT0("cc", "RasterBufferImpl::Playback");
     // GPU raster doesn't do low res tiles, so should always include images.
     DCHECK(!playback_settings.skip_images);
-    ContextProvider* context_provider = rasterizer_->resource_provider()
-                                            ->output_surface()
-                                            ->worker_context_provider();
-    DCHECK(context_provider);
 
-    ContextProvider::ScopedContextLock scoped_context(context_provider);
+    ContextProvider::ScopedContextLock scoped_context(
+        rasterizer_->worker_context_provider());
 
     gfx::Rect playback_rect = raster_full_rect;
     if (resource_has_previous_content_) {
@@ -88,26 +85,19 @@
 
 }  // namespace
 
-// static
-std::unique_ptr<RasterBufferProvider> GpuRasterBufferProvider::Create(
-    ContextProvider* context_provider,
-    ResourceProvider* resource_provider,
-    bool use_distance_field_text,
-    int gpu_rasterization_msaa_sample_count) {
-  return base::WrapUnique<RasterBufferProvider>(new GpuRasterBufferProvider(
-      context_provider, resource_provider, use_distance_field_text,
-      gpu_rasterization_msaa_sample_count));
-}
-
 GpuRasterBufferProvider::GpuRasterBufferProvider(
-    ContextProvider* context_provider,
+    ContextProvider* compositor_context_provider,
+    ContextProvider* worker_context_provider,
     ResourceProvider* resource_provider,
     bool use_distance_field_text,
     int gpu_rasterization_msaa_sample_count)
-    : rasterizer_(new GpuRasterizer(context_provider,
+    : compositor_context_provider_(compositor_context_provider),
+      rasterizer_(new GpuRasterizer(worker_context_provider,
                                     resource_provider,
                                     use_distance_field_text,
-                                    gpu_rasterization_msaa_sample_count)) {}
+                                    gpu_rasterization_msaa_sample_count)) {
+  DCHECK(compositor_context_provider_);
+}
 
 GpuRasterBufferProvider::~GpuRasterBufferProvider() {}
 
@@ -126,12 +116,7 @@
 
 void GpuRasterBufferProvider::OrderingBarrier() {
   TRACE_EVENT0("cc", "GpuRasterBufferProvider::OrderingBarrier");
-
-  rasterizer_->resource_provider()
-      ->output_surface()
-      ->context_provider()
-      ->ContextGL()
-      ->OrderingBarrierCHROMIUM();
+  compositor_context_provider_->ContextGL()->OrderingBarrierCHROMIUM();
 }
 
 ResourceFormat GpuRasterBufferProvider::GetResourceFormat(