Unify MacOS resizing path with glResizeCHROMIUM.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=97644

Review URL: http://codereview.chromium.org/7671035

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@97668 0039d316-1c4b-4281-b951-d872f2087c98

10 files changed, 174 insertions, 204 deletions

diff --git a/gpu/command_buffer/build_gles2_cmd_buffer.py b/gpu/command_buffer/build_gles2_cmd_buffer.py
index 574897e..b09e24a 100755
--- a/gpu/command_buffer/build_gles2_cmd_buffer.py
+++ b/gpu/command_buffer/build_gles2_cmd_buffer.py
@@ -1727,7 +1727,8 @@ _FUNCTION_INFO = {
                   'GLsizei stride, GLuint offset',
   },
   'ResizeCHROMIUM': {
-      'decoder_func': 'DoResizeCHROMIUM',
+      'type': 'Custom',
+      'impl_func': False,
       'unit_test': False,
       'extension': True,
       'chromium': True,
diff --git a/gpu/command_buffer/client/gles2_implementation.cc b/gpu/command_buffer/client/gles2_implementation.cc
index e34e476..956ac62 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -2482,6 +2482,12 @@ void GLES2Implementation::UnmapTexSubImage2DCHROMIUM(const void* mem) {
   mapped_textures_.erase(it);
 }
 
+void GLES2Implementation::ResizeCHROMIUM(GLuint width, GLuint height) {
+  GPU_CLIENT_LOG("[" << this << "] glResizeCHROMIUM("
+                 << width << ", " << height << ")");
+  helper_->ResizeCHROMIUM(width, height);
+}
+
 const GLchar* GLES2Implementation::GetRequestableExtensionsCHROMIUM() {
   GPU_CLIENT_LOG("[" << this << "] glGetRequestableExtensionsCHROMIUM()");
   TRACE_EVENT0("gpu",
@@ -2625,4 +2631,3 @@ void GLES2Implementation::GetProgramInfoCHROMIUM(
 
 }  // namespace gles2
 }  // namespace gpu
-
diff --git a/gpu/command_buffer/client/gles2_implementation_autogen.h b/gpu/command_buffer/client/gles2_implementation_autogen.h
index ba061a5..021e3e9 100644
--- a/gpu/command_buffer/client/gles2_implementation_autogen.h
+++ b/gpu/command_buffer/client/gles2_implementation_autogen.h
@@ -1254,10 +1254,7 @@ void* MapTexSubImage2DCHROMIUM(
 
 void UnmapTexSubImage2DCHROMIUM(const void* mem);
 
-void ResizeCHROMIUM(GLuint width, GLuint height) {
-  GPU_CLIENT_LOG("[" << this << "] glResizeCHROMIUM(" << width << ", " << height << ")");  // NOLINT
-  helper_->ResizeCHROMIUM(width, height);
-}
+void ResizeCHROMIUM(GLuint width, GLuint height);
 
 const GLchar* GetRequestableExtensionsCHROMIUM();
 
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 4f35103..5e500bb 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -468,8 +468,7 @@ class GLES2DecoderImpl : public base::SupportsWeakPtr<GLES2DecoderImpl>,
   virtual void Destroy();
   virtual bool SetParent(GLES2Decoder* parent_decoder,
                          uint32 parent_texture_id);
-  virtual void ResizeOffscreenFrameBuffer(const gfx::Size& size);
-  virtual bool UpdateOffscreenFrameBufferSize();
+  virtual bool ResizeOffscreenFrameBuffer(const gfx::Size& size);
   void UpdateParentTextureInfo();
   virtual bool MakeCurrent();
   virtual GLES2Util* GetGLES2Util() { return &util_; }
@@ -1035,8 +1034,6 @@ class GLES2DecoderImpl : public base::SupportsWeakPtr<GLES2DecoderImpl>,
   // Wrapper for glValidateProgram.
   void DoValidateProgram(GLuint program_client_id);
 
-  void DoResizeCHROMIUM(GLuint width, GLuint height);
-
   void DoSetSurfaceCHROMIUM(GLint surface_id);
 
   // Gets the number of values that will be returned by glGetXXX. Returns
@@ -1181,10 +1178,6 @@ class GLES2DecoderImpl : public base::SupportsWeakPtr<GLES2DecoderImpl>,
   // The parent pointer is reset if the parent is destroyed.
   base::WeakPtr<GLES2DecoderImpl> parent_;
 
-  // Width and height to which an offscreen frame buffer should be resized on
-  // the next call to SwapBuffers.
-  gfx::Size pending_offscreen_size_;
-
   // Current width and height of the offscreen frame buffer.
   gfx::Size offscreen_size_;
 
@@ -1917,8 +1910,7 @@ bool GLES2DecoderImpl::Initialize(
 
     // Allocate the render buffers at their initial size and check the status
     // of the frame buffers is okay.
-    pending_offscreen_size_ = size;
-    if (!UpdateOffscreenFrameBufferSize()) {
+    if (!ResizeOffscreenFrameBuffer(size)) {
       LOG(ERROR) << "Could not allocate offscreen buffer storage.";
       Destroy();
       return false;
@@ -2226,140 +2218,6 @@ GLenum GLES2DecoderImpl::GetBoundDrawFrameBufferInternalFormat() {
   }
 }
 
-bool GLES2DecoderImpl::UpdateOffscreenFrameBufferSize() {
-  if (offscreen_size_ == pending_offscreen_size_)
-    return true;
-
-  offscreen_size_ = pending_offscreen_size_;
-  int w = offscreen_size_.width();
-  int h = offscreen_size_.height();
-  if (w < 0 || h < 0 || h >= (INT_MAX / 4) / (w ? w : 1)) {
-    LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-               << "to allocate storage due to excessive dimensions.";
-    return false;
-  }
-
-  // Reallocate the offscreen target buffers.
-  DCHECK(offscreen_target_color_format_);
-  if (IsOffscreenBufferMultisampled()) {
-    if (!offscreen_target_color_render_buffer_->AllocateStorage(
-        pending_offscreen_size_, offscreen_target_color_format_,
-        offscreen_target_samples_)) {
-      LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-                 << "to allocate storage for offscreen target color buffer.";
-      return false;
-    }
-  } else {
-    if (!offscreen_target_color_texture_->AllocateStorage(
-        pending_offscreen_size_, offscreen_target_color_format_)) {
-      LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-                 << "to allocate storage for offscreen target color texture.";
-      return false;
-    }
-  }
-  if (offscreen_target_depth_format_ &&
-      !offscreen_target_depth_render_buffer_->AllocateStorage(
-      pending_offscreen_size_, offscreen_target_depth_format_,
-      offscreen_target_samples_)) {
-    LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-               << "to allocate storage for offscreen target depth buffer.";
-    return false;
-  }
-  if (offscreen_target_stencil_format_ &&
-      !offscreen_target_stencil_render_buffer_->AllocateStorage(
-      pending_offscreen_size_, offscreen_target_stencil_format_,
-      offscreen_target_samples_)) {
-    LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-               << "to allocate storage for offscreen target stencil buffer.";
-    return false;
-  }
-
-  // Attach the offscreen target buffers to the target frame buffer.
-  if (IsOffscreenBufferMultisampled()) {
-    offscreen_target_frame_buffer_->AttachRenderBuffer(
-        GL_COLOR_ATTACHMENT0,
-        offscreen_target_color_render_buffer_.get());
-  } else {
-    offscreen_target_frame_buffer_->AttachRenderTexture(
-        offscreen_target_color_texture_.get());
-  }
-  if (offscreen_target_depth_format_) {
-    offscreen_target_frame_buffer_->AttachRenderBuffer(
-        GL_DEPTH_ATTACHMENT,
-        offscreen_target_depth_render_buffer_.get());
-  }
-  const bool packed_depth_stencil =
-      offscreen_target_depth_format_ == GL_DEPTH24_STENCIL8;
-  if (packed_depth_stencil) {
-    offscreen_target_frame_buffer_->AttachRenderBuffer(
-        GL_STENCIL_ATTACHMENT,
-        offscreen_target_depth_render_buffer_.get());
-  } else if (offscreen_target_stencil_format_) {
-    offscreen_target_frame_buffer_->AttachRenderBuffer(
-        GL_STENCIL_ATTACHMENT,
-        offscreen_target_stencil_render_buffer_.get());
-  }
-
-  if (offscreen_target_frame_buffer_->CheckStatus() !=
-      GL_FRAMEBUFFER_COMPLETE) {
-      LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-                 << "because offscreen FBO was incomplete.";
-    return false;
-  }
-
-  // Clear the target frame buffer.
-  {
-    ScopedFrameBufferBinder binder(this, offscreen_target_frame_buffer_->id());
-    glClearColor(0, 0, 0, (GLES2Util::GetChannelsForFormat(
-        offscreen_target_color_format_) & 0x0008) != 0 ? 0 : 1);
-    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
-    glClearStencil(0);
-    glStencilMaskSeparate(GL_FRONT, -1);
-    glStencilMaskSeparate(GL_BACK, -1);
-    glClearDepth(0);
-    glDepthMask(GL_TRUE);
-    glDisable(GL_SCISSOR_TEST);
-    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
-    RestoreClearState();
-  }
-
-  // Allocate the offscreen saved color texture.
-  DCHECK(offscreen_saved_color_format_);
-  offscreen_saved_color_texture_->AllocateStorage(
-      pending_offscreen_size_, offscreen_saved_color_format_);
-
-  offscreen_saved_frame_buffer_->AttachRenderTexture(
-      offscreen_saved_color_texture_.get());
-  if (offscreen_saved_frame_buffer_->CheckStatus() !=
-      GL_FRAMEBUFFER_COMPLETE) {
-    LOG(ERROR) << "GLES2DecoderImpl::UpdateOffscreenFrameBufferSize failed "
-               << "because offscreen saved FBO was incomplete.";
-    return false;
-  }
-
-  // Destroy the offscreen resolved framebuffers.
-  if (offscreen_resolved_frame_buffer_.get())
-    offscreen_resolved_frame_buffer_->Destroy();
-  if (offscreen_resolved_color_texture_.get())
-    offscreen_resolved_color_texture_->Destroy();
-  offscreen_resolved_color_texture_.reset();
-  offscreen_resolved_frame_buffer_.reset();
-
-  // Clear the offscreen color texture.
-  {
-    ScopedFrameBufferBinder binder(this, offscreen_saved_frame_buffer_->id());
-    glClearColor(0, 0, 0, 0);
-    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
-    glDisable(GL_SCISSOR_TEST);
-    glClear(GL_COLOR_BUFFER_BIT);
-    RestoreClearState();
-  }
-
-  UpdateParentTextureInfo();
-
-  return true;
-}
-
 void GLES2DecoderImpl::UpdateParentTextureInfo() {
   if (parent_) {
     // Update the info about the offscreen saved color texture in the parent.
@@ -2378,8 +2236,8 @@ void GLES2DecoderImpl::UpdateParentTextureInfo() {
         GL_TEXTURE_2D,
         0,  // level
         GL_RGBA,
-        pending_offscreen_size_.width(),
-        pending_offscreen_size_.height(),
+        offscreen_size_.width(),
+        offscreen_size_.height(),
         1,  // depth
         0,  // border
         GL_RGBA,
@@ -2407,7 +2265,8 @@ void GLES2DecoderImpl::UpdateParentTextureInfo() {
   }
 }
 
-void GLES2DecoderImpl::SetResizeCallback(Callback1<gfx::Size>::Type* callback) {
+void GLES2DecoderImpl::SetResizeCallback(
+    Callback1<gfx::Size>::Type* callback) {
   resize_callback_.reset(callback);
 }
 
@@ -2553,22 +2412,166 @@ bool GLES2DecoderImpl::SetParent(GLES2Decoder* new_parent,
   return true;
 }
 
-void GLES2DecoderImpl::ResizeOffscreenFrameBuffer(const gfx::Size& size) {
-  // We can't resize the render buffers immediately because there might be a
-  // partial frame rendered into them and we don't want the tail end of that
-  // rendered into the reallocated storage. Defer until the next SwapBuffers.
-  pending_offscreen_size_ = size;
+bool GLES2DecoderImpl::ResizeOffscreenFrameBuffer(const gfx::Size& size) {
+  bool is_offscreen = !!offscreen_target_frame_buffer_.get();
+  if (!is_offscreen) {
+    LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer called "
+               << " with an onscreen framebuffer.";
+    return false;
+  }
+
+  if (offscreen_size_ == size)
+    return true;
+
+  offscreen_size_ = size;
+  int w = offscreen_size_.width();
+  int h = offscreen_size_.height();
+  if (w < 0 || h < 0 || h >= (INT_MAX / 4) / (w ? w : 1)) {
+    LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+               << "to allocate storage due to excessive dimensions.";
+    return false;
+  }
+
+  // Reallocate the offscreen target buffers.
+  DCHECK(offscreen_target_color_format_);
+  if (IsOffscreenBufferMultisampled()) {
+    if (!offscreen_target_color_render_buffer_->AllocateStorage(
+        offscreen_size_, offscreen_target_color_format_,
+        offscreen_target_samples_)) {
+      LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+                 << "to allocate storage for offscreen target color buffer.";
+      return false;
+    }
+  } else {
+    if (!offscreen_target_color_texture_->AllocateStorage(
+        offscreen_size_, offscreen_target_color_format_)) {
+      LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+                 << "to allocate storage for offscreen target color texture.";
+      return false;
+    }
+  }
+  if (offscreen_target_depth_format_ &&
+      !offscreen_target_depth_render_buffer_->AllocateStorage(
+      offscreen_size_, offscreen_target_depth_format_,
+      offscreen_target_samples_)) {
+    LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+               << "to allocate storage for offscreen target depth buffer.";
+    return false;
+  }
+  if (offscreen_target_stencil_format_ &&
+      !offscreen_target_stencil_render_buffer_->AllocateStorage(
+      offscreen_size_, offscreen_target_stencil_format_,
+      offscreen_target_samples_)) {
+    LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+               << "to allocate storage for offscreen target stencil buffer.";
+    return false;
+  }
+
+  // Attach the offscreen target buffers to the target frame buffer.
+  if (IsOffscreenBufferMultisampled()) {
+    offscreen_target_frame_buffer_->AttachRenderBuffer(
+        GL_COLOR_ATTACHMENT0,
+        offscreen_target_color_render_buffer_.get());
+  } else {
+    offscreen_target_frame_buffer_->AttachRenderTexture(
+        offscreen_target_color_texture_.get());
+  }
+  if (offscreen_target_depth_format_) {
+    offscreen_target_frame_buffer_->AttachRenderBuffer(
+        GL_DEPTH_ATTACHMENT,
+        offscreen_target_depth_render_buffer_.get());
+  }
+  const bool packed_depth_stencil =
+      offscreen_target_depth_format_ == GL_DEPTH24_STENCIL8;
+  if (packed_depth_stencil) {
+    offscreen_target_frame_buffer_->AttachRenderBuffer(
+        GL_STENCIL_ATTACHMENT,
+        offscreen_target_depth_render_buffer_.get());
+  } else if (offscreen_target_stencil_format_) {
+    offscreen_target_frame_buffer_->AttachRenderBuffer(
+        GL_STENCIL_ATTACHMENT,
+        offscreen_target_stencil_render_buffer_.get());
+  }
+
+  if (offscreen_target_frame_buffer_->CheckStatus() !=
+      GL_FRAMEBUFFER_COMPLETE) {
+      LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+                 << "because offscreen FBO was incomplete.";
+    return false;
+  }
+
+  // Clear the target frame buffer.
+  {
+    ScopedFrameBufferBinder binder(this, offscreen_target_frame_buffer_->id());
+    glClearColor(0, 0, 0, (GLES2Util::GetChannelsForFormat(
+        offscreen_target_color_format_) & 0x0008) != 0 ? 0 : 1);
+    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+    glClearStencil(0);
+    glStencilMaskSeparate(GL_FRONT, -1);
+    glStencilMaskSeparate(GL_BACK, -1);
+    glClearDepth(0);
+    glDepthMask(GL_TRUE);
+    glDisable(GL_SCISSOR_TEST);
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
+    RestoreClearState();
+  }
+
+  // Allocate the offscreen saved color texture.
+  DCHECK(offscreen_saved_color_format_);
+  offscreen_saved_color_texture_->AllocateStorage(
+      offscreen_size_, offscreen_saved_color_format_);
+
+  offscreen_saved_frame_buffer_->AttachRenderTexture(
+      offscreen_saved_color_texture_.get());
+  if (offscreen_saved_frame_buffer_->CheckStatus() !=
+      GL_FRAMEBUFFER_COMPLETE) {
+    LOG(ERROR) << "GLES2DecoderImpl::ResizeOffscreenFrameBuffer failed "
+               << "because offscreen saved FBO was incomplete.";
+    return false;
+  }
+
+  // Destroy the offscreen resolved framebuffers.
+  if (offscreen_resolved_frame_buffer_.get())
+    offscreen_resolved_frame_buffer_->Destroy();
+  if (offscreen_resolved_color_texture_.get())
+    offscreen_resolved_color_texture_->Destroy();
+  offscreen_resolved_color_texture_.reset();
+  offscreen_resolved_frame_buffer_.reset();
+
+  // Clear the offscreen color texture.
+  {
+    ScopedFrameBufferBinder binder(this, offscreen_saved_frame_buffer_->id());
+    glClearColor(0, 0, 0, 0);
+    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+    glDisable(GL_SCISSOR_TEST);
+    glClear(GL_COLOR_BUFFER_BIT);
+    RestoreClearState();
+  }
+
+  UpdateParentTextureInfo();
+
+  return true;
 }
 
-void GLES2DecoderImpl::DoResizeCHROMIUM(GLuint width, GLuint height) {
+error::Error GLES2DecoderImpl::HandleResizeCHROMIUM(
+    uint32 immediate_data_size, const gles2::ResizeCHROMIUM& c) {
+  GLuint width = static_cast<GLuint>(c.width);
+  GLuint height = static_cast<GLuint>(c.height);
+  TRACE_EVENT2("gpu", "glResizeChromium", "width", width, "height", height);
 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(TOUCH_UI)
   // Make sure that we are done drawing to the back buffer before resizing.
   glFinish();
 #endif
-  if (resize_callback_.get()) {
-    gfx::Size size(width, height);
-    resize_callback_->Run(size);
+  bool is_offscreen = !!offscreen_target_frame_buffer_.get();
+  if (is_offscreen) {
+    if (!ResizeOffscreenFrameBuffer(gfx::Size(width, height)))
+      return error::kLostContext;
   }
+
+  if (resize_callback_.get())
+    resize_callback_->Run(gfx::Size(width, height));
+
+  return error::kNoError;
 }
 
 void GLES2DecoderImpl::DoSetSurfaceCHROMIUM(GLint surface_id) {
@@ -6554,14 +6557,6 @@ error::Error GLES2DecoderImpl::HandleSwapBuffers(
   if (is_offscreen) {
     ScopedGLErrorSuppressor suppressor(this);
 
-    // First check to see if a deferred offscreen render buffer resize is
-    // pending.
-    if (!UpdateOffscreenFrameBufferSize()) {
-      LOG(ERROR) << "Context lost because reallocation of offscreen FBO "
-                 << "failed.";
-      return error::kLostContext;
-    }
-
     if (IsOffscreenBufferMultisampled()) {
       // For multisampled buffers, bind the resolved frame buffer so that
       // callbacks can call ReadPixels or CopyTexImage2D.
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.h b/gpu/command_buffer/service/gles2_cmd_decoder.h
index 23c5e3a..fc66b3d 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.h
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.h
@@ -81,12 +81,7 @@ class GLES2Decoder : public CommonDecoder {
                          uint32 parent_texture_id) = 0;
 
   // Resize an offscreen frame buffer.
-  virtual void ResizeOffscreenFrameBuffer(const gfx::Size& size) = 0;
-
-  // Force the offscreen frame buffer's size to be updated. This
-  // usually occurs lazily, during SwapBuffers, but on some platforms
-  // (Mac OS X in particular) it must be done immediately.
-  virtual bool UpdateOffscreenFrameBufferSize() = 0;
+  virtual bool ResizeOffscreenFrameBuffer(const gfx::Size& size) = 0;
 
   // Make this decoder's GL context current.
   virtual bool MakeCurrent() = 0;
@@ -105,7 +100,8 @@ class GLES2Decoder : public CommonDecoder {
 
   // Sets a callback which is called when a glResizeCHROMIUM command
   // is processed.
-  virtual void SetResizeCallback(Callback1<gfx::Size>::Type* callback) = 0;
+  virtual void SetResizeCallback(
+      Callback1<gfx::Size>::Type* callback) = 0;
 
   // Sets a callback which is called when a SwapBuffers command is processed.
   virtual void SetSwapBuffersCallback(Callback0::Type* callback) = 0;
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_autogen.h b/gpu/command_buffer/service/gles2_cmd_decoder_autogen.h
index 9023cfe..27ef39b 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_autogen.h
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_autogen.h
@@ -2568,14 +2568,6 @@ error::Error GLES2DecoderImpl::HandleGetMaxValueInBufferCHROMIUM(
   return error::kNoError;
 }
 
-error::Error GLES2DecoderImpl::HandleResizeCHROMIUM(
-    uint32 immediate_data_size, const gles2::ResizeCHROMIUM& c) {
-  GLuint width = static_cast<GLuint>(c.width);
-  GLuint height = static_cast<GLuint>(c.height);
-  DoResizeCHROMIUM(width, height);
-  return error::kNoError;
-}
-
 error::Error GLES2DecoderImpl::HandleSetSurfaceCHROMIUM(
     uint32 immediate_data_size, const gles2::SetSurfaceCHROMIUM& c) {
   GLint surface_id = static_cast<GLint>(c.surface_id);
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_mock.h b/gpu/command_buffer/service/gles2_cmd_decoder_mock.h
index 13e60bb..fa9d43d 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_mock.h
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_mock.h
@@ -38,8 +38,7 @@ class MockGLES2Decoder : public GLES2Decoder {
                     const std::vector<int32>& attribs));
   MOCK_METHOD0(Destroy, void());
   MOCK_METHOD2(SetParent, bool(GLES2Decoder* parent, uint32 parent_texture_id));
-  MOCK_METHOD1(ResizeOffscreenFrameBuffer, void(const gfx::Size& size));
-  MOCK_METHOD0(UpdateOffscreenFrameBufferSize, bool());
+  MOCK_METHOD1(ResizeOffscreenFrameBuffer, bool(const gfx::Size& size));
   MOCK_METHOD0(MakeCurrent, bool());
   MOCK_METHOD1(GetServiceIdForTesting, uint32(uint32 client_id));
   MOCK_METHOD0(GetGLES2Util, GLES2Util*());
diff --git a/gpu/command_buffer/service/gpu_scheduler.cc b/gpu/command_buffer/service/gpu_scheduler.cc
index 15316ea..6413cc1 100644
--- a/gpu/command_buffer/service/gpu_scheduler.cc
+++ b/gpu/command_buffer/service/gpu_scheduler.cc
@@ -228,11 +228,8 @@ int32 GpuScheduler::GetGetOffset() {
   return parser_->get();
 }
 
-void GpuScheduler::ResizeOffscreenFrameBuffer(const gfx::Size& size) {
-  decoder_->ResizeOffscreenFrameBuffer(size);
-}
-
-void GpuScheduler::SetResizeCallback(Callback1<gfx::Size>::Type* callback) {
+void GpuScheduler::SetResizeCallback(
+    Callback1<gfx::Size>::Type* callback) {
   decoder_->SetResizeCallback(callback);
 }
 
diff --git a/gpu/command_buffer/service/gpu_scheduler.h b/gpu/command_buffer/service/gpu_scheduler.h
index 75ccc63..61c60be 100644
--- a/gpu/command_buffer/service/gpu_scheduler.h
+++ b/gpu/command_buffer/service/gpu_scheduler.h
@@ -98,9 +98,6 @@ class GpuScheduler : public CommandBufferEngine {
   virtual bool SetGetOffset(int32 offset);
   virtual int32 GetGetOffset();
 
-  // Asynchronously resizes an offscreen frame buffer.
-  void ResizeOffscreenFrameBuffer(const gfx::Size& size);
-
 #if defined(OS_MACOSX)
   // To prevent the GPU process from overloading the browser process,
   // we need to track the number of swap buffers calls issued and
diff --git a/gpu/command_buffer/service/gpu_scheduler_mac.cc b/gpu/command_buffer/service/gpu_scheduler_mac.cc
index cfa0d5c..2efa9cb 100644
--- a/gpu/command_buffer/service/gpu_scheduler_mac.cc
+++ b/gpu/command_buffer/service/gpu_scheduler_mac.cc
@@ -74,21 +74,12 @@ void GpuScheduler::Destroy() {
 }
 
 uint64 GpuScheduler::SetWindowSizeForIOSurface(const gfx::Size& size) {
-  // This is called from an IPC handler, so it's undefined which context is
-  // current. Make sure the right one is.
-  decoder_->GetGLContext()->MakeCurrent(decoder_->GetGLSurface());
-
-  ResizeOffscreenFrameBuffer(size);
-  decoder_->UpdateOffscreenFrameBufferSize();
-
   // Note: The following line changes the current context again.
   return surface_->SetSurfaceSize(size);
 }
 
 TransportDIB::Handle GpuScheduler::SetWindowSizeForTransportDIB(
     const gfx::Size& size) {
-  ResizeOffscreenFrameBuffer(size);
-  decoder_->UpdateOffscreenFrameBufferSize();
   return surface_->SetTransportDIBSize(size);
 }