Add support for compressed GPU memory buffers.

content/common/gpu/gpu_command_buffer_stub.cc

Index: content/common/gpu/gpu_command_buffer_stub.cc
diff --git a/content/common/gpu/gpu_command_buffer_stub.cc b/content/common/gpu/gpu_command_buffer_stub.cc
index 6503c679b07d4ea263806db03e53d4a18038d9b2..e7962a5dafa02202df6f43b598e4c15876792a75 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -956,6 +956,41 @@ void GpuCommandBufferStub::OnCreateImage(int32 id,
     return;
   }
 
+  bool supported_format = true;
+
+  gpu::Capabilities capabilities = decoder_->GetCapabilities();
+  switch (format) {
+    case gfx::GpuMemoryBuffer::ATC:
+    case gfx::GpuMemoryBuffer::ATCIA:
+      if (!capabilities.texture_format_atc)
+        supported_format = false;
+      break;
+    case gfx::GpuMemoryBuffer::BGRA_8888:
+      if (!capabilities.texture_format_bgra8888)
+        supported_format = false;
+      break;
+    case gfx::GpuMemoryBuffer::DXT1:
+      if (!capabilities.texture_format_dxt1)
+        supported_format = false;
+      break;
+    case gfx::GpuMemoryBuffer::DXT5:
+      if (!capabilities.texture_format_dxt5)
+        supported_format = false;
+      break;
+    case gfx::GpuMemoryBuffer::ETC1:
+      if (!capabilities.texture_format_etc1)
+        supported_format = false;
+      break;
+    case gfx::GpuMemoryBuffer::RGBA_8888:
+    case gfx::GpuMemoryBuffer::RGBX_8888:
+      break;
+  }

[reveman, 2015/02/13 23:51:25]

Looks good. Can you just move this into a IsSupportedImageFormat helper function
with

NOTREACHED();
return false;

at the end? I think that would be a bit cleaner and we'd also detect if format
was ever an invalid value.

[christiank, 2015/02/18 14:38:25]

Sure! I'll fix this.

+
+  if (!supported_format) {
+    LOG(ERROR) << "Image format is not supported.";
+    return;
+  }
+
   scoped_refptr<gfx::GLImage> image = channel()->CreateImageForGpuMemoryBuffer(
       handle, size, format, internalformat);
   if (!image.get())