Remove --no-use-mus-in-renderer

content/browser/compositor/gpu_process_transport_factory.cc

Index: content/browser/compositor/gpu_process_transport_factory.cc
diff --git a/content/browser/compositor/gpu_process_transport_factory.cc b/content/browser/compositor/gpu_process_transport_factory.cc
index 2d6a2d6bac0914b55091cc7be27045f39e3474b1..670dbb2b9c126d0f688a4ab547dfa933c8ce880a 100644
--- a/content/browser/compositor/gpu_process_transport_factory.cc
+++ b/content/browser/compositor/gpu_process_transport_factory.cc
@@ -62,7 +62,6 @@
 #include "ui/gl/gl_switches.h"
 
 #if defined(USE_AURA)
-#include "content/browser/compositor/mus_browser_compositor_output_surface.h"
 #include "content/public/common/service_manager_connection.h"
 #include "ui/aura/window_tree_host.h"
 #endif
@@ -110,10 +109,6 @@ const int kNumRetriesBeforeSoftwareFallback = 4;
 // from RenderWidgetHostImpl.
 constexpr uint32_t kDefaultClientId = 0u;
 
-bool IsUsingMus() {
-  return service_manager::ServiceManagerIsRemote();
-}
-
 bool IsGpuVSyncSignalSupported() {
 #if defined(OS_WIN)
   // TODO(stanisc): http://crbug.com/467617 Limit to Windows 8+ for now because
@@ -298,9 +293,6 @@ static bool ShouldCreateGpuCompositorFrameSink(ui::Compositor* compositor) {
   // Software fallback does not happen on Chrome OS.
   return true;
 #endif
-  if (IsUsingMus())
-    return true;
-
 #if defined(OS_WIN)
   if (::GetProp(compositor->widget(), kForceSoftwareCompositor) &&
       ::RemoveProp(compositor->widget(), kForceSoftwareCompositor))
@@ -361,7 +353,7 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
   DCHECK(data);
 
   if (num_attempts > kNumRetriesBeforeSoftwareFallback) {
-    bool fatal = IsUsingMus();
+    bool fatal = false;
 #if defined(OS_CHROMEOS)
     fatal = true;
 #endif
@@ -436,9 +428,8 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
         // use CommandBufferProxyImpl::TakeFrontBuffer() to take the context's
         // front buffer into a mailbox, insert a sync token, and send the
         // mailbox+sync to the ui service process.
-        gpu::SurfaceHandle surface_handle =
-            IsUsingMus() ? gpu::kNullSurfaceHandle : data->surface_handle;
-        bool need_alpha_channel = IsUsingMus();
+        gpu::SurfaceHandle surface_handle = data->surface_handle;
+        bool need_alpha_channel = false;
         bool support_locking = false;
         context_provider = CreateContextCommon(
             std::move(gpu_channel_host), surface_handle, need_alpha_channel,
@@ -537,36 +528,15 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
       } else {
         std::unique_ptr<display_compositor::CompositorOverlayCandidateValidator>
             validator;
-        const bool use_mus = IsUsingMus();
 #if !defined(OS_MACOSX)
         // Overlays are only supported on surfaceless output surfaces on Mac.
-        if (!use_mus)
-          validator = CreateOverlayCandidateValidator(compositor->widget());
-#endif
-        if (!use_mus) {
-          auto gpu_output_surface =
-              base::MakeUnique<GpuBrowserCompositorOutputSurface>(
-                  context_provider, vsync_callback, std::move(validator));
-          gpu_vsync_control = gpu_output_surface.get();
-          display_output_surface = std::move(gpu_output_surface);
-        } else {
-#if defined(USE_AURA)
-          aura::WindowTreeHost* host =
-              aura::WindowTreeHost::GetForAcceleratedWidget(
-                  compositor->widget());
-          auto mus_output_surface =
-              base::MakeUnique<MusBrowserCompositorOutputSurface>(
-                  host->window(), context_provider, GetGpuMemoryBufferManager(),
-                  vsync_callback, std::move(validator));
-          // We use the ExternalBeginFrameSource provided by the output surface
-          // instead of our own synthetic one.
-          begin_frame_source = mus_output_surface->GetBeginFrameSource();

[stanisc, 2017/03/28 18:14:23]

Now that this line of code is removed it doesn't make sense to declare
begin_frame_source further above.

-          DCHECK(begin_frame_source);
-          display_output_surface = std::move(mus_output_surface);
-#else
-          NOTREACHED();
+        validator = CreateOverlayCandidateValidator(compositor->widget());
 #endif
-        }
+        auto gpu_output_surface =
+            base::MakeUnique<GpuBrowserCompositorOutputSurface>(
+                context_provider, vsync_callback, std::move(validator));
+        gpu_vsync_control = gpu_output_surface.get();
+        display_output_surface = std::move(gpu_output_surface);
       }
     }
   }