Add initial GLImage tracing + stubs

ui/gl/gl_image_shared_memory.cc

Index: ui/gl/gl_image_shared_memory.cc
diff --git a/ui/gl/gl_image_shared_memory.cc b/ui/gl/gl_image_shared_memory.cc
index 469a6f98d1c242a89e71792eb2c240ceb3d318c8..372790996f5f7509b35d56d8087f6ac8b7189015 100644
--- a/ui/gl/gl_image_shared_memory.cc
+++ b/ui/gl/gl_image_shared_memory.cc
@@ -33,8 +33,7 @@ bool SizeInBytes(const gfx::Size& size,
 
 GLImageSharedMemory::GLImageSharedMemory(const gfx::Size& size,
                                          unsigned internalformat)
-    : GLImageMemory(size, internalformat) {
-}
+    : GLImageMemory(size, internalformat) {}
 
 GLImageSharedMemory::~GLImageSharedMemory() {
   DCHECK(!shared_memory_);
@@ -73,6 +72,7 @@ bool GLImageSharedMemory::Initialize(const gfx::GpuMemoryBufferHandle& handle,
 
   DCHECK(!shared_memory_);
   shared_memory_ = duped_shared_memory.Pass();
+  shared_memory_id_ = handle.id;
   return true;
 }
 
@@ -81,4 +81,22 @@ void GLImageSharedMemory::Destroy(bool have_context) {
   shared_memory_.reset();
 }
 
+void GLImageSharedMemory::DumpMemory(base::trace_event::ProcessMemoryDump* pmd,
+                                     uint64_t process_tracing_id,
+                                     const std::string& dump_name) {
+  size_t size_bytes;
+  SizeInBytes(GetSize(), format(), &size_bytes);
+
+  base::trace_event::MemoryAllocatorDump* dump =
+      pmd->CreateAllocatorDump(dump_name);
+  dump->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
+                  base::trace_event::MemoryAllocatorDump::kUnitsBytes,
+                  static_cast<uint64_t>(size_bytes));
+
+  auto guid = base::trace_event::GetGenericSharedMemoryGUIDForTracing(
+      process_tracing_id, shared_memory_id_);
+  pmd->CreateSharedGlobalAllocatorDump(guid);
+  pmd->AddOwnershipEdge(dump->guid(), guid);
+}
+
 }  // namespace gfx