Add GPU memory tab to the task manager.

content/common/gpu/gpu_memory_tracking.h

Index: content/common/gpu/gpu_memory_tracking.h
diff --git a/content/common/gpu/gpu_memory_tracking.h b/content/common/gpu/gpu_memory_tracking.h
new file mode 100644
index 0000000000000000000000000000000000000000..c20ad850f675999bd39163dcc72aeb21b086007f
--- /dev/null
+++ b/content/common/gpu/gpu_memory_tracking.h
@@ -0,0 +1,53 @@
+// Copyright (c) 2012 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.
+
+#ifndef CONTENT_COMMON_GPU_GPU_MEMORY_TRACKING_H_
+#define CONTENT_COMMON_GPU_GPU_MEMORY_TRACKING_H_
+
+#if defined(ENABLE_GPU)
+
+#include "base/basictypes.h"
+#include "content/common/gpu/gpu_memory_manager.h"
+
+// All decoders in a context group point to a single GpuMemoryTrackingGroup,
+// which tracks GPU resource consumption for the entire context group.
+class GpuMemoryTrackingGroup {
+ public:
+  GpuMemoryTrackingGroup(base::ProcessId pid, GpuMemoryManager* memory_manager)
+      : pid_(pid),
+        size_(0),
+        memory_manager_(memory_manager) {
+    memory_manager_->AddTrackingGroup(this);
+  }
+  ~GpuMemoryTrackingGroup() {
+    memory_manager_->RemoveTrackingGroup(this);
+  }
+  void TrackMemoryAllocatedChange(size_t old_size, size_t new_size) {
+    if (old_size < new_size) {
+      size_t delta = new_size - old_size;
+      size_ += delta;
+    }
+    if (new_size < old_size) {
+      size_t delta = old_size - new_size;
+      DCHECK(size_ >= delta);
+      size_ -= delta;
+    }
+    memory_manager_->TrackMemoryAllocatedChange(old_size, new_size);
+  }
+  base::ProcessId GetPid() const {
+    return pid_;
+  }
+  size_t GetSize() const {
+    return size_;
+  }
+
+ private:
+  base::ProcessId pid_;
+  size_t size_;
+  GpuMemoryManager* memory_manager_;
+};
+
+#endif
+
+#endif // CONTENT_COMMON_GPU_GPU_MEMORY_TRACKING_H_