Change CHROMIUM_image declarations to support multi planar input.

content/browser/compositor/buffer_queue.cc

Index: content/browser/compositor/buffer_queue.cc
diff --git a/content/browser/compositor/buffer_queue.cc b/content/browser/compositor/buffer_queue.cc
index 689288f6d63b75d10c0b329fb32205d234ee1140..e42d937e802b8e2c397e177b50603b72ce732639 100644
--- a/content/browser/compositor/buffer_queue.cc
+++ b/content/browser/compositor/buffer_queue.cc
@@ -4,6 +4,7 @@
 
 #include "content/browser/compositor/buffer_queue.h"
 
+#include "base/memory/scoped_vector.h"
 #include "content/browser/compositor/image_transport_factory.h"
 #include "content/browser/gpu/browser_gpu_memory_buffer_manager.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
@@ -167,19 +168,32 @@ BufferQueue::AllocatedSurface BufferQueue::GetNextSurface() {
   // We don't want to allow anything more than triple buffering.
   DCHECK_LT(allocated_count_, 4U);
 
-  scoped_ptr<gfx::GpuMemoryBuffer> buffer(
-      gpu_memory_buffer_manager_->AllocateGpuMemoryBufferForScanout(
-          size_, gpu::ImageFactory::ImageFormatToGpuMemoryBufferFormat(
-                     internalformat_),
-          surface_id_));
-  if (!buffer) {
-    gl->DeleteTextures(1, &texture);
-    DLOG(ERROR) << "Failed to allocate GPU memory buffer";
-    return AllocatedSurface();
+  std::vector<gfx::GpuMemoryBuffer::Format> gpu_memory_buffer_formats;
+  gpu::ImageFactory::ImageFormatToGpuMemoryBufferFormats(
+      internalformat_, &gpu_memory_buffer_formats);
+  int num_buffers = gpu_memory_buffer_formats.size();
+
+  DCHECK_GE(num_buffers, 1);

[reveman, 2015/03/04 05:56:00]

I think it's correct to assume that the number of buffers are one in this case.
As we can assume that, why deal with all these vectors here? The old code with
just one buffer should be sufficient.

[emircan, 2015/03/04 23:31:50]

I agree that it is 1 currently. But if we were to support
CreateGpuMemoryBufferImageCHROMIUM with GL_RGB_YUV420 wouldn't we need to back
it with multiple buffers?

[reveman, 2015/03/05 19:35:31]

I read the DCHECK wrong in my initial comment. I think this should be
DCHECK_EQ(num_buffers, 1) as I don't think it makes for this specific code to
ever support multi-plane buffers. The buffer queue is explicitly for single
plane RGB buffers.

[emircan, 2015/03/09 21:07:22]

Done. Reverted to original single buffer usage.

+
+  ScopedVector<gfx::GpuMemoryBuffer> buffers;
+  ClientBuffer client_buffers[num_buffers];
+  for (int i = 0; i < num_buffers; ++i) {
+    buffers.push_back(
+        gpu_memory_buffer_manager_->AllocateGpuMemoryBufferForScanout(
+            size_, gpu_memory_buffer_formats[i],
+            surface_id_));
+
+    if (!buffers[i]) {
+      gl->DeleteTextures(1, &texture);
+      DLOG(ERROR) << "Failed to allocate GPU memory buffer";
+      return AllocatedSurface();
+    }
+
+    client_buffers[i] = buffers[i]->AsClientBuffer();
   }
 
-  unsigned int id = gl->CreateImageCHROMIUM(
-      buffer->AsClientBuffer(), size_.width(), size_.height(), internalformat_);
+  unsigned int id = gl->CreateImageCHROMIUM(client_buffers, size_.width(),
+                                            size_.height(), internalformat_);
 
   if (!id) {
     LOG(ERROR) << "Failed to allocate backing image surface";