Update GPU memory buffers to use StrideInBytes internally.

content/common/gpu/gpu_memory_buffer_factory_io_surface.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/gpu/gpu_memory_buffer_factory_io_surface.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 
 #include "base/logging.h"
 #include "ui/gl/gl_image_io_surface.h"
@@ skipping 76 matching lines @@
 }
 
 gfx::GpuMemoryBufferHandle
 GpuMemoryBufferFactoryIOSurface::CreateGpuMemoryBuffer(
     gfx::GpuMemoryBufferId id,
     const gfx::Size& size,
     gfx::GpuMemoryBuffer::Format format,
     gfx::GpuMemoryBuffer::Usage usage,
     int client_id,
     gfx::PluginWindowHandle surface_handle) {
+  size_t width_in_bytes =
+      GpuMemoryBufferImpl::StrideInBytes(size.width(), format);
+  DCHECK_EQ(width_in_bytes % size.width(), 0u);
   base::ScopedCFTypeRef<CFMutableDictionaryRef> properties;
   properties.reset(CFDictionaryCreateMutable(kCFAllocatorDefault,
                                              0,
                                              &kCFTypeDictionaryKeyCallBacks,
                                              &kCFTypeDictionaryValueCallBacks));
   AddIntegerValue(properties, kIOSurfaceWidth, size.width());
   AddIntegerValue(properties, kIOSurfaceHeight, size.height());
-  AddIntegerValue(properties, kIOSurfaceBytesPerElement, BytesPerPixel(format));
+  AddIntegerValue(properties, kIOSurfaceBytesPerElement,
+                  width_in_bytes / size.width());

[reveman, 2014/12/18 18:49:57]

nit: Please keep using BytesPerPixel here instead. Deriving bpp from the stride
feels backwards and fragile. I think it's fine that some implementations don't
use StrideInBytes. Maybe just DCHECK_EQ(BytesPerPixel(format) * width,
StrideInBytes(width, format)) if we're using StrideInBytes in
GpuMemoryBufferImplIOSurface.

[christiank, 2015/01/12 10:35:22]

Alright, I missed that this file actually had its own BytesPerPixel function.

   AddIntegerValue(properties, kIOSurfacePixelFormat, PixelFormat(format));
   // TODO(reveman): Remove this when using a mach_port_t to transfer
   // IOSurface to browser and renderer process. crbug.com/323304
   AddBooleanValue(properties, kIOSurfaceIsGlobal, true);
 
   base::ScopedCFTypeRef<IOSurfaceRef> io_surface(IOSurfaceCreate(properties));
   if (!io_surface)
     return gfx::GpuMemoryBufferHandle();
 
   {
@@ skipping 42 matching lines @@
     return scoped_refptr<gfx::GLImage>();
 
   scoped_refptr<gfx::GLImageIOSurface> image(new gfx::GLImageIOSurface(size));
   if (!image->Initialize(it->second.get()))
     return scoped_refptr<gfx::GLImage>();
 
   return image;
 }
 
 }  // namespace content