Move a bunch of code in content\common (as well as a few left in renderer) to the content namespace.

content/common/gpu/media/gpu_video_decode_accelerator.cc

Index: content/common/gpu/media/gpu_video_decode_accelerator.cc
===================================================================
--- content/common/gpu/media/gpu_video_decode_accelerator.cc	(revision 163290)
+++ content/common/gpu/media/gpu_video_decode_accelerator.cc	(working copy)
@@ -36,6 +36,8 @@
 
 using gpu::gles2::TextureManager;
 
+namespace content {
+
 static bool MakeDecoderContextCurrent(
     const base::WeakPtr<GpuCommandBufferStub> stub) {
   if (!stub) {
@@ -304,3 +306,5 @@
   DCHECK(sender_);
   return sender_->Send(message);
 }
+
+}  // namespace content