Change glimage to accept a type.

content/common/gpu/client/gpu_memory_buffer_impl_mac.cc

Index: content/common/gpu/client/gpu_memory_buffer_impl_mac.cc
diff --git a/content/common/gpu/client/gpu_memory_buffer_impl_mac.cc b/content/common/gpu/client/gpu_memory_buffer_impl_mac.cc
index 1c8e5521a01e678e32b4c84d3cb69be2689604bb..633fd20e9263ddfa718bf1f4deeb4b1fb33b6b4b 100644
--- a/content/common/gpu/client/gpu_memory_buffer_impl_mac.cc
+++ b/content/common/gpu/client/gpu_memory_buffer_impl_mac.cc
@@ -12,7 +12,11 @@ namespace content {
 scoped_ptr<GpuMemoryBufferImpl> GpuMemoryBufferImpl::Create(
     gfx::GpuMemoryBufferHandle handle,
     gfx::Size size,
-    unsigned internalformat) {
+    unsigned internalformat,
+    unsigned usage) {
+  if (usage == gfx::GpuMemoryBuffer::SCANOUT)
+    return scoped_ptr<GpuMemoryBufferImpl>();
+
   switch (handle.type) {
     case gfx::SHARED_MEMORY_BUFFER: {
       scoped_ptr<GpuMemoryBufferImplShm> buffer(