gpu: Associate all GpuMemoryBuffers with unique IDs.

content/browser/gpu/browser_gpu_memory_buffer_manager.cc

Index: content/browser/gpu/browser_gpu_memory_buffer_manager.cc
diff --git a/content/browser/gpu/browser_gpu_memory_buffer_manager.cc b/content/browser/gpu/browser_gpu_memory_buffer_manager.cc
index 373713dbfe29b7def404eec7aeaa649083a104c4..07d2feff4ebc729834c1a37b1abd692476067504 100644
--- a/content/browser/gpu/browser_gpu_memory_buffer_manager.cc
+++ b/content/browser/gpu/browser_gpu_memory_buffer_manager.cc
@@ -4,6 +4,7 @@
 
 #include "content/browser/gpu/browser_gpu_memory_buffer_manager.h"
 
+#include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
@@ -25,6 +26,9 @@ void GpuMemoryBufferAllocatedForChildProcess(
 
 BrowserGpuMemoryBufferManager* g_gpu_memory_buffer_manager = nullptr;
 
+// Global atomic to generate gpu memory buffer unique IDs.
+base::StaticAtomicSequenceNumber g_next_gpu_memory_buffer_id;
+
 }  // namespace
 
 struct BrowserGpuMemoryBufferManager::AllocateGpuMemoryBufferRequest {
@@ -93,6 +97,7 @@ void BrowserGpuMemoryBufferManager::AllocateGpuMemoryBufferForChildProcess(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   GpuMemoryBufferImpl::AllocateForChildProcess(
+      g_next_gpu_memory_buffer_id.GetNext(),
       size,
       format,
       usage,
@@ -109,7 +114,7 @@ BrowserGpuMemoryBufferManager::GpuMemoryBufferFromClientBuffer(
 
 void BrowserGpuMemoryBufferManager::ChildProcessDeletedGpuMemoryBuffer(
     gfx::GpuMemoryBufferType type,
-    const gfx::GpuMemoryBufferId& id,
+    gfx::GpuMemoryBufferId id,
     base::ProcessHandle child_process_handle,
     int child_client_id,
     uint32 sync_point) {
@@ -128,6 +133,7 @@ void BrowserGpuMemoryBufferManager::ProcessRemoved(
 void BrowserGpuMemoryBufferManager::AllocateGpuMemoryBufferOnIO(
     AllocateGpuMemoryBufferRequest* request) {
   GpuMemoryBufferImpl::Create(
+      g_next_gpu_memory_buffer_id.GetNext(),
       request->size,
       request->format,
       request->usage,