Add multi-planar functions to GpuMemoryBuffer

content/common/gpu/client/gpu_memory_buffer_impl_io_surface.cc

Index: content/common/gpu/client/gpu_memory_buffer_impl_io_surface.cc
diff --git a/content/common/gpu/client/gpu_memory_buffer_impl_io_surface.cc b/content/common/gpu/client/gpu_memory_buffer_impl_io_surface.cc
index e8ac048e15d79994ffba7017424c0f6ee753c5ae..8df55a3f53610f4d75ed4fefd10dd33d97165dcf 100644
--- a/content/common/gpu/client/gpu_memory_buffer_impl_io_surface.cc
+++ b/content/common/gpu/client/gpu_memory_buffer_impl_io_surface.cc
@@ -42,6 +42,12 @@ void* GpuMemoryBufferImplIOSurface::Map() {
   return IOSurfaceGetBaseAddress(io_surface_);
 }
 
+void* GpuMemoryBufferImplIOSurface::Map(size_t plane_index) {
+  if (plane_index >= num_planes_)
+    return NULL;
+  return Map();
+}
+
 void GpuMemoryBufferImplIOSurface::Unmap() {
   DCHECK(mapped_);
   IOSurfaceUnlock(io_surface_, 0, NULL);
@@ -52,6 +58,12 @@ uint32 GpuMemoryBufferImplIOSurface::GetStride() const {
   return IOSurfaceGetBytesPerRow(io_surface_);
 }
 
+uint32 GpuMemoryBufferImplIOSurface::GetStride(size_t plane_index) const {
+  if (plane_index >= num_planes_)
+    return 0;
+  return GetStride();
+}
+
 gfx::GpuMemoryBufferHandle GpuMemoryBufferImplIOSurface::GetHandle() const {
   gfx::GpuMemoryBufferHandle handle;
   handle.type = gfx::IO_SURFACE_BUFFER;