Remove always-on compositor capabilities

All context implementations the compositor uses support the following
capabilities:

- discard_backbuffer
- set_visibility
- map_sub
- shallow_flush

so there's no point in passing these values or, even worse, branching
on them.

R=piman

Review URL: https://codereview.chromium.org/94113004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239171 0039d316-1c4b-4281-b951-d872f2087c98

21 files changed, 27 insertions, 109 deletions

diff --git a/cc/output/context_provider.cc b/cc/output/context_provider.cc
index e8e5c9d..454d96b 100644
--- a/cc/output/context_provider.cc
+++ b/cc/output/context_provider.cc
@@ -9,15 +9,11 @@
 namespace cc {
 
 ContextProvider::Capabilities::Capabilities()
-    : discard_backbuffer(false),
-      egl_image_external(false),
+    : egl_image_external(false),
       fast_npot_mo8_textures(false),
       iosurface(false),
       map_image(false),
-      map_sub(false),
       post_sub_buffer(false),
-      set_visibility(false),
-      shallow_flush(false),
       swapbuffers_complete_callback(false),
       texture_format_bgra8888(false),
       texture_format_etc1(false),
@@ -29,15 +25,11 @@ ContextProvider::Capabilities::Capabilities()
 
 ContextProvider::Capabilities::Capabilities(
     const gpu::Capabilities& gpu_capabilities)
-    : discard_backbuffer(false),
-      egl_image_external(gpu_capabilities.egl_image_external),
+    : egl_image_external(gpu_capabilities.egl_image_external),
       fast_npot_mo8_textures(gpu_capabilities.fast_npot_mo8_textures),
       iosurface(gpu_capabilities.iosurface),
       map_image(gpu_capabilities.map_image),
-      map_sub(false),
       post_sub_buffer(gpu_capabilities.post_sub_buffer),
-      set_visibility(false),
-      shallow_flush(false),
       swapbuffers_complete_callback(false),
       texture_format_bgra8888(gpu_capabilities.texture_format_bgra8888),
       texture_format_etc1(gpu_capabilities.texture_format_etc1),
diff --git a/cc/output/context_provider.h b/cc/output/context_provider.h
index 8649421..09b1835 100644
--- a/cc/output/context_provider.h
+++ b/cc/output/context_provider.h
@@ -34,15 +34,11 @@ class ContextProvider : public base::RefCountedThreadSafe<ContextProvider> {
   virtual class GrContext* GrContext() = 0;
 
   struct Capabilities {
-    bool discard_backbuffer : 1;
     bool egl_image_external : 1;
     bool fast_npot_mo8_textures : 1;
     bool iosurface : 1;
     bool map_image : 1;
-    bool map_sub : 1;
     bool post_sub_buffer : 1;
-    bool set_visibility : 1;
-    bool shallow_flush : 1;
     bool swapbuffers_complete_callback : 1;
     bool texture_format_bgra8888 : 1;
     bool texture_format_etc1 : 1;
diff --git a/cc/output/delegating_renderer.cc b/cc/output/delegating_renderer.cc
index 918491d..001b7fd 100644
--- a/cc/output/delegating_renderer.cc
+++ b/cc/output/delegating_renderer.cc
@@ -78,7 +78,6 @@ bool DelegatingRenderer::Initialize() {
 
   DCHECK(!caps.iosurface || caps.texture_rectangle);
 
-  capabilities_.using_set_visibility = caps.set_visibility;
   capabilities_.using_egl_image = caps.egl_image_external;
   capabilities_.using_map_image = settings_->use_map_image && caps.map_image;
 
@@ -162,13 +161,11 @@ void DelegatingRenderer::SetVisible(bool visible) {
     if (context_provider)
       context_provider->Context3d()->flush();
   }
-  if (capabilities_.using_set_visibility) {
-    // We loop visibility to the GPU process, since that's what manages memory.
-    // That will allow it to feed us with memory allocations that we can act
-    // upon.
-    DCHECK(context_provider);
-    context_provider->Context3d()->setVisibilityCHROMIUM(visible);
-  }
+  // We loop visibility to the GPU process, since that's what manages memory.
+  // That will allow it to feed us with memory allocations that we can act
+  // upon.
+  DCHECK(context_provider);
+  context_provider->Context3d()->setVisibilityCHROMIUM(visible);
 }
 
 void DelegatingRenderer::SendManagedMemoryStats(size_t bytes_visible,
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 3bf0d5b..16bdd31 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -202,8 +202,6 @@ bool GLRenderer::Initialize() {
   capabilities_.using_partial_swap =
       settings_->partial_swap_enabled && context_caps.post_sub_buffer;
 
-  capabilities_.using_set_visibility = context_caps.set_visibility;
-
   DCHECK(!context_caps.iosurface || context_caps.texture_rectangle);
 
   capabilities_.using_egl_image = context_caps.egl_image_external;
@@ -283,8 +281,7 @@ void GLRenderer::SetVisible(bool visible) {
   // TODO(jamesr): Replace setVisibilityCHROMIUM() with an extension to
   // explicitly manage front/backbuffers
   // crbug.com/116049
-  if (capabilities_.using_set_visibility)
-    context_->setVisibilityCHROMIUM(visible);
+  context_->setVisibilityCHROMIUM(visible);
 }
 
 void GLRenderer::SendManagedMemoryStats(size_t bytes_visible,
diff --git a/cc/output/gl_renderer_unittest.cc b/cc/output/gl_renderer_unittest.cc
index 6288c5d..773768e 100644
--- a/cc/output/gl_renderer_unittest.cc
+++ b/cc/output/gl_renderer_unittest.cc
@@ -132,10 +132,7 @@ TEST_F(GLRendererShaderPixelTest, AllShadersCompile) { TestShaders(); }
 class FrameCountingContext : public TestWebGraphicsContext3D {
  public:
   FrameCountingContext()
-      : frame_(0) {
-    test_capabilities_.set_visibility = true;
-    test_capabilities_.discard_backbuffer = true;
-  }
+      : frame_(0) {}
 
   // WebGraphicsContext3D methods.
 
@@ -738,10 +735,7 @@ class VisibilityChangeIsLastCallTrackingContext
     : public TestWebGraphicsContext3D {
  public:
   VisibilityChangeIsLastCallTrackingContext()
-      : last_call_was_set_visibility_(false) {
-    test_capabilities_.set_visibility = true;
-    test_capabilities_.discard_backbuffer = true;
-  }
+      : last_call_was_set_visibility_(false) {}
 
   // WebGraphicsContext3D methods.
   virtual void setVisibilityCHROMIUM(bool visible) {
@@ -1599,7 +1593,6 @@ TEST_F(GLRendererShaderTest, DrawSolidColorShader) {
 class OutputSurfaceMockContext : public TestWebGraphicsContext3D {
  public:
   OutputSurfaceMockContext() {
-    test_capabilities_.discard_backbuffer = true;
     test_capabilities_.post_sub_buffer = true;
   }
 
diff --git a/cc/output/output_surface.cc b/cc/output/output_surface.cc
index 749527e..7c56eea 100644
--- a/cc/output/output_surface.cc
+++ b/cc/output/output_surface.cc
@@ -44,7 +44,6 @@ namespace cc {
 
 OutputSurface::OutputSurface(scoped_refptr<ContextProvider> context_provider)
     : context_provider_(context_provider),
-      has_gl_discard_backbuffer_(false),
       has_swap_buffers_complete_callback_(false),
       device_scale_factor_(-1),
       max_frames_pending_(0),
@@ -60,7 +59,6 @@ OutputSurface::OutputSurface(scoped_refptr<ContextProvider> context_provider)
 OutputSurface::OutputSurface(
     scoped_ptr<cc::SoftwareOutputDevice> software_device)
     : software_device_(software_device.Pass()),
-      has_gl_discard_backbuffer_(false),
       has_swap_buffers_complete_callback_(false),
       device_scale_factor_(-1),
       max_frames_pending_(0),
@@ -78,7 +76,6 @@ OutputSurface::OutputSurface(
     scoped_ptr<cc::SoftwareOutputDevice> software_device)
     : context_provider_(context_provider),
       software_device_(software_device.Pass()),
-      has_gl_discard_backbuffer_(false),
       has_swap_buffers_complete_callback_(false),
       device_scale_factor_(-1),
       max_frames_pending_(0),
@@ -320,7 +317,6 @@ void OutputSurface::SetUpContext3d() {
   const ContextProvider::Capabilities& caps =
       context_provider_->ContextCapabilities();
 
-  has_gl_discard_backbuffer_ = caps.discard_backbuffer;
   has_swap_buffers_complete_callback_ = caps.swapbuffers_complete_callback;
 
   context_provider_->SetLostContextCallback(
@@ -356,14 +352,14 @@ void OutputSurface::ResetContext3d() {
 }
 
 void OutputSurface::EnsureBackbuffer() {
-  if (context_provider_ && has_gl_discard_backbuffer_)
+  if (context_provider_)
     context_provider_->Context3d()->ensureBackbufferCHROMIUM();
   if (software_device_)
     software_device_->EnsureBackbuffer();
 }
 
 void OutputSurface::DiscardBackbuffer() {
-  if (context_provider_ && has_gl_discard_backbuffer_)
+  if (context_provider_)
     context_provider_->Context3d()->discardBackbufferCHROMIUM();
   if (software_device_)
     software_device_->DiscardBackbuffer();
diff --git a/cc/output/output_surface.h b/cc/output/output_surface.h
index efe0ea2..d724465 100644
--- a/cc/output/output_surface.h
+++ b/cc/output/output_surface.h
@@ -154,7 +154,6 @@ class CC_EXPORT OutputSurface : public FrameRateControllerClient {
   struct cc::OutputSurface::Capabilities capabilities_;
   scoped_refptr<ContextProvider> context_provider_;
   scoped_ptr<cc::SoftwareOutputDevice> software_device_;
-  bool has_gl_discard_backbuffer_;
   bool has_swap_buffers_complete_callback_;
   gfx::Size surface_size_;
   float device_scale_factor_;
diff --git a/cc/output/software_renderer.cc b/cc/output/software_renderer.cc
index 3cc4e29..421e541 100644
--- a/cc/output/software_renderer.cc
+++ b/cc/output/software_renderer.cc
@@ -86,7 +86,6 @@ SoftwareRenderer::SoftwareRenderer(RendererClient* client,
     capabilities_.best_texture_format =
         resource_provider_->best_texture_format();
   }
-  capabilities_.using_set_visibility = true;
   // The updater can access bitmaps while the SoftwareRenderer is using them.
   capabilities_.allow_partial_texture_updates = true;
   capabilities_.using_partial_swap = true;
diff --git a/cc/resources/resource_provider.cc b/cc/resources/resource_provider.cc
index f5d365f..a725b4f 100644
--- a/cc/resources/resource_provider.cc
+++ b/cc/resources/resource_provider.cc
@@ -712,7 +712,7 @@ void ResourceProvider::Finish() {
 bool ResourceProvider::ShallowFlushIfSupported() {
   DCHECK(thread_checker_.CalledOnValidThread());
   WebGraphicsContext3D* context3d = Context3d();
-  if (!context3d || !use_shallow_flush_)
+  if (!context3d)
     return false;
 
   context3d->shallowFlushCHROMIUM();
@@ -899,7 +899,6 @@ ResourceProvider::ResourceProvider(OutputSurface* output_surface,
       default_resource_type_(InvalidType),
       use_texture_storage_ext_(false),
       use_texture_usage_hint_(false),
-      use_shallow_flush_(false),
       use_compressed_texture_etc1_(false),
       max_texture_size_(0),
       best_texture_format_(RGBA_8888),
@@ -938,15 +937,12 @@ bool ResourceProvider::InitializeGL() {
   const ContextProvider::Capabilities& caps =
       output_surface_->context_provider()->ContextCapabilities();
 
-  bool use_map_sub = caps.map_sub;
   bool use_bgra = caps.texture_format_bgra8888;
   use_texture_storage_ext_ = caps.texture_storage;
-  use_shallow_flush_ = caps.shallow_flush;
   use_texture_usage_hint_ = caps.texture_usage;
   use_compressed_texture_etc1_ = caps.texture_format_etc1;
 
-  texture_uploader_ =
-      TextureUploader::Create(context3d, use_map_sub, use_shallow_flush_);
+  texture_uploader_ = TextureUploader::Create(context3d);
   max_texture_size_ = 0;  // Context expects cleared value.
   GLC(context3d, context3d->getIntegerv(GL_MAX_TEXTURE_SIZE,
                                         &max_texture_size_));
diff --git a/cc/resources/resource_provider.h b/cc/resources/resource_provider.h
index 53a3747..21207c0 100644
--- a/cc/resources/resource_provider.h
+++ b/cc/resources/resource_provider.h
@@ -488,7 +488,6 @@ class CC_EXPORT ResourceProvider {
   ResourceType default_resource_type_;
   bool use_texture_storage_ext_;
   bool use_texture_usage_hint_;
-  bool use_shallow_flush_;
   bool use_compressed_texture_etc1_;
   scoped_ptr<TextureUploader> texture_uploader_;
   int max_texture_size_;
diff --git a/cc/resources/resource_update_controller_unittest.cc b/cc/resources/resource_update_controller_unittest.cc
index c824d21..a28f251 100644
--- a/cc/resources/resource_update_controller_unittest.cc
+++ b/cc/resources/resource_update_controller_unittest.cc
@@ -35,9 +35,7 @@ class ResourceUpdateControllerTest;
 class WebGraphicsContext3DForUploadTest : public TestWebGraphicsContext3D {
  public:
   explicit WebGraphicsContext3DForUploadTest(ResourceUpdateControllerTest* test)
-      : test_(test) {
-    test_capabilities_.shallow_flush = true;
-  }
+      : test_(test) {}
 
   virtual void flush() OVERRIDE;
   virtual void shallowFlushCHROMIUM() OVERRIDE;
diff --git a/cc/scheduler/texture_uploader.cc b/cc/scheduler/texture_uploader.cc
index 54d3515..ff941b2 100644
--- a/cc/scheduler/texture_uploader.cc
+++ b/cc/scheduler/texture_uploader.cc
@@ -74,14 +74,10 @@ unsigned TextureUploader::Query::Value() {
   return value_;
 }
 
-TextureUploader::TextureUploader(blink::WebGraphicsContext3D* context,
-                                 bool use_map_tex_sub_image,
-                                 bool use_shallow_flush)
+TextureUploader::TextureUploader(blink::WebGraphicsContext3D* context)
     : context_(context),
       num_blocking_texture_uploads_(0),
-      use_map_tex_sub_image_(use_map_tex_sub_image),
       sub_image_size_(0),
-      use_shallow_flush_(use_shallow_flush),
       num_texture_uploads_since_last_flush_(0) {
   for (size_t i = kUploadHistorySizeInitial; i > 0; i--)
     textures_per_second_history_.insert(kDefaultEstimatedTexturesPerSecond);
@@ -148,13 +144,8 @@ void TextureUploader::Upload(const uint8* image,
     DCHECK(is_full_upload);
     UploadWithTexImageETC1(image, size);
   } else {
-    if (use_map_tex_sub_image_) {
-      UploadWithMapTexSubImage(
-          image, image_rect, source_rect, dest_offset, format);
-    } else {
-      UploadWithTexSubImage(
-          image, image_rect, source_rect, dest_offset, format);
-    }
+    UploadWithMapTexSubImage(
+        image, image_rect, source_rect, dest_offset, format);
   }
 
   if (is_full_upload)
@@ -169,8 +160,7 @@ void TextureUploader::Flush() {
   if (!num_texture_uploads_since_last_flush_)
     return;
 
-  if (use_shallow_flush_)
-    context_->shallowFlushCHROMIUM();
+  context_->shallowFlushCHROMIUM();
 
   num_texture_uploads_since_last_flush_ = 0;
 }
diff --git a/cc/scheduler/texture_uploader.h b/cc/scheduler/texture_uploader.h
index 66e60c1..77c4449 100644
--- a/cc/scheduler/texture_uploader.h
+++ b/cc/scheduler/texture_uploader.h
@@ -25,12 +25,9 @@ namespace cc {
 
 class CC_EXPORT TextureUploader {
  public:
-  static scoped_ptr<TextureUploader> Create(
-      blink::WebGraphicsContext3D* context,
-      bool use_map_tex_sub_image,
-      bool use_shallow_flush) {
-    return make_scoped_ptr(
-        new TextureUploader(context, use_map_tex_sub_image, use_shallow_flush));
+  static scoped_ptr<TextureUploader>
+  Create(blink::WebGraphicsContext3D* context) {
+    return make_scoped_ptr(new TextureUploader(context));
   }
   ~TextureUploader();
 
@@ -85,9 +82,7 @@ class CC_EXPORT TextureUploader {
     DISALLOW_COPY_AND_ASSIGN(Query);
   };
 
-  TextureUploader(blink::WebGraphicsContext3D* context,
-                  bool use_map_tex_sub_image,
-                  bool use_shallow_flush);
+  explicit TextureUploader(blink::WebGraphicsContext3D* context);
 
   void BeginQuery();
   void EndQuery();
@@ -111,11 +106,9 @@ class CC_EXPORT TextureUploader {
   std::multiset<double> textures_per_second_history_;
   size_t num_blocking_texture_uploads_;
 
-  bool use_map_tex_sub_image_;
   size_t sub_image_size_;
   scoped_ptr<uint8[]> sub_image_;
 
-  bool use_shallow_flush_;
   size_t num_texture_uploads_since_last_flush_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureUploader);
diff --git a/cc/scheduler/texture_uploader_unittest.cc b/cc/scheduler/texture_uploader_unittest.cc
index 5d5bf1f..b7fb084 100644
--- a/cc/scheduler/texture_uploader_unittest.cc
+++ b/cc/scheduler/texture_uploader_unittest.cc
@@ -166,7 +166,7 @@ TEST(TextureUploaderTest, NumBlockingUploads) {
   scoped_ptr<TestWebGraphicsContext3DTextureUpload> fake_context(
       new TestWebGraphicsContext3DTextureUpload);
   scoped_ptr<TextureUploader> uploader =
-      TextureUploader::Create(fake_context.get(), false, false);
+      TextureUploader::Create(fake_context.get());
 
   fake_context->SetResultAvailable(0);
   EXPECT_EQ(0u, uploader->NumBlockingUploads());
@@ -188,7 +188,7 @@ TEST(TextureUploaderTest, MarkPendingUploadsAsNonBlocking) {
   scoped_ptr<TestWebGraphicsContext3DTextureUpload> fake_context(
       new TestWebGraphicsContext3DTextureUpload);
   scoped_ptr<TextureUploader> uploader =
-      TextureUploader::Create(fake_context.get(), false, false);
+      TextureUploader::Create(fake_context.get());
 
   fake_context->SetResultAvailable(0);
   EXPECT_EQ(0u, uploader->NumBlockingUploads());
@@ -212,7 +212,7 @@ TEST(TextureUploaderTest, UploadContentsTest) {
   scoped_ptr<TestWebGraphicsContext3DTextureUpload> fake_context(
       new TestWebGraphicsContext3DTextureUpload);
   scoped_ptr<TextureUploader> uploader =
-      TextureUploader::Create(fake_context.get(), false, false);
+      TextureUploader::Create(fake_context.get());
   uint8 buffer[256 * 256 * 4];
 
   // Upload a tightly packed 256x256 RGBA texture.
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index fc9209e..081d96b 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -50,7 +50,6 @@ namespace cc {
 RendererCapabilities::RendererCapabilities()
     : best_texture_format(RGBA_8888),
       using_partial_swap(false),
-      using_set_visibility(false),
       using_egl_image(false),
       allow_partial_texture_updates(false),
       using_offscreen_context3d(false),
diff --git a/cc/trees/layer_tree_host.h b/cc/trees/layer_tree_host.h
index 53ec30e..b1fb0c6 100644
--- a/cc/trees/layer_tree_host.h
+++ b/cc/trees/layer_tree_host.h
@@ -67,7 +67,6 @@ struct CC_EXPORT RendererCapabilities {
 
   ResourceFormat best_texture_format;
   bool using_partial_swap;
-  bool using_set_visibility;
   bool using_egl_image;
   bool allow_partial_texture_updates;
   bool using_offscreen_context3d;
diff --git a/content/common/gpu/client/context_provider_command_buffer.cc b/content/common/gpu/client/context_provider_command_buffer.cc
index 5ee350e..1e14b2e 100644
--- a/content/common/gpu/client/context_provider_command_buffer.cc
+++ b/content/common/gpu/client/context_provider_command_buffer.cc
@@ -215,17 +215,7 @@ void ContextProviderCommandBuffer::OnMemoryAllocationChanged(
 }
 
 void ContextProviderCommandBuffer::InitializeCapabilities() {
-  // The command buffer provides the following capabilities always.
-  // TODO(jamesr): This information is duplicated with
-  // gpu::gles2::FeatureInfo::AddFeatures().
   Capabilities caps(context3d_->GetImplementation()->capabilities());
-  caps.discard_backbuffer = true;
-  caps.set_visibility = true;
-
-  // TODO(jamesr): These are also added in
-  // gpu::gles2::GLES2Implementation::GetStringHelper() on the client side.
-  caps.map_sub = true;
-  caps.shallow_flush = true;
 
   // The swapbuffers complete callback is always supported by multi-process
   // command buffer implementations.
diff --git a/gpu/command_buffer/client/gles2_implementation.cc b/gpu/command_buffer/client/gles2_implementation.cc
index 1e97f19..6f6798f 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -2129,8 +2129,6 @@ const GLubyte* GLES2Implementation::GetStringHelper(GLenum name) {
       case GL_EXTENSIONS:
         str += std::string(str.empty() ? "" : " ") +
             "GL_CHROMIUM_flipy "
-            "GL_CHROMIUM_map_sub "
-            "GL_CHROMIUM_shallow_flush "
             "GL_EXT_unpack_subimage";
         if (capabilities_.map_image) {
           // The first space character is intentional.
diff --git a/gpu/command_buffer/client/gles2_implementation_unittest.cc b/gpu/command_buffer/client/gles2_implementation_unittest.cc
index f2d4dbc..5bc0c71 100644
--- a/gpu/command_buffer/client/gles2_implementation_unittest.cc
+++ b/gpu/command_buffer/client/gles2_implementation_unittest.cc
@@ -2479,8 +2479,6 @@ TEST_F(GLES2ImplementationTest, GetString) {
   const char* expected_str =
       "foobar "
       "GL_CHROMIUM_flipy "
-      "GL_CHROMIUM_map_sub "
-      "GL_CHROMIUM_shallow_flush "
       "GL_EXT_unpack_subimage";
   const char kBad = 0x12;
   struct Cmds {
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index 57db99b..c9f0733 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -237,14 +237,12 @@ void FeatureInfo::InitializeFeatures() {
   AddExtensionString("GL_CHROMIUM_command_buffer_query");
   AddExtensionString("GL_CHROMIUM_command_buffer_latency_query");
   AddExtensionString("GL_CHROMIUM_copy_texture");
-  AddExtensionString("GL_CHROMIUM_discard_backbuffer");
   AddExtensionString("GL_CHROMIUM_get_error_query");
   AddExtensionString("GL_CHROMIUM_lose_context");
   AddExtensionString("GL_CHROMIUM_pixel_transfer_buffer_object");
   AddExtensionString("GL_CHROMIUM_rate_limit_offscreen_context");
   AddExtensionString("GL_CHROMIUM_resize");
   AddExtensionString("GL_CHROMIUM_resource_safe");
-  AddExtensionString("GL_CHROMIUM_set_visibility");
   AddExtensionString("GL_CHROMIUM_strict_attribs");
   AddExtensionString("GL_CHROMIUM_stream_texture");
   AddExtensionString("GL_CHROMIUM_texture_mailbox");
diff --git a/webkit/common/gpu/context_provider_in_process.cc b/webkit/common/gpu/context_provider_in_process.cc
index c9098a7..fcca0e7 100644
--- a/webkit/common/gpu/context_provider_in_process.cc
+++ b/webkit/common/gpu/context_provider_in_process.cc
@@ -123,16 +123,7 @@ bool ContextProviderInProcess::BindToCurrentThread() {
 }
 
 void ContextProviderInProcess::InitializeCapabilities() {
-  Capabilities caps(context3d_->GetImplementation()->capabilities());
-
-  // We always use a WebGraphicsContext3DInProcessCommandBufferImpl which
-  // provides the following capabilities:
-  caps.discard_backbuffer = true;
-  caps.map_sub = true;
-  caps.set_visibility = true;
-  caps.shallow_flush = true;
-
-  capabilities_ = caps;
+  capabilities_ = Capabilities(context3d_->GetImplementation()->capabilities());
 }
 
 cc::ContextProvider::Capabilities