initialize trace_event hooks in angle on gpu startup

ui/gl/gl_implementation_win.cc

Index: ui/gl/gl_implementation_win.cc
diff --git a/ui/gl/gl_implementation_win.cc b/ui/gl/gl_implementation_win.cc
index c98c3c013143e111b2ccaca5709151cb2efc7680..6040b8e64aead208733fb719897995002c11b1d5 100644
--- a/ui/gl/gl_implementation_win.cc
+++ b/ui/gl/gl_implementation_win.cc
@@ -8,6 +8,7 @@
 #include "base/base_paths.h"
 #include "base/bind.h"
 #include "base/command_line.h"
+#include "base/debug/trace_event.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/native_library.h"
@@ -58,6 +59,45 @@ bool LoadD3DXLibrary(const base::FilePath& module_path,
   return true;
 }
 
+const unsigned char* AngleGetTraceCategoryEnabledFlag(const char* name) {
+  return TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(name);
+}
+
+void AngleAddTraceEvent(char phase,
+                        const unsigned char* category_group_enabled,
+                        const char* name,
+                        unsigned long long id,
+                        int num_args,
+                        const char** arg_names,
+                        const unsigned char* arg_types,
+                        const unsigned long long* arg_values,
+                        unsigned char flags) {
+  TRACE_EVENT_API_ADD_TRACE_EVENT(phase,
+                                  category_group_enabled,
+                                  name,
+                                  id,
+                                  num_args,
+                                  arg_names,
+                                  arg_types,
+                                  arg_values,
+                                  NULL,
+                                  flags);
+}
+
+typedef const unsigned char* (*GetCategoryEnabledFlagFunc)(const char* name);
+typedef void (*AddTraceEventFunc)(char phase,
+                                  const unsigned char* categoryGroupEnabled,
+                                  const char* name,
+                                  unsigned long long id,
+                                  int numArgs,
+                                  const char** argNames,
+                                  const unsigned char* argTypes,
+                                  const unsigned long long* argValues,
+                                  unsigned char flags);
+typedef void (*SetTraceFunctionPointersFunc)(
+    GetCategoryEnabledFlagFunc get_category_enabled_flag,
+    AddTraceEventFunc add_trace_event_func);
+
 }  // namespace
 
 void GetAllowedGLImplementations(std::vector<GLImplementation>* impls) {
@@ -167,6 +207,17 @@ bool InitializeGLBindings(GLImplementation implementation) {
       }
 #endif
 
+      if (!using_swift_shader) {
+        SetTraceFunctionPointersFunc set_trace_function_pointers =
+            reinterpret_cast<SetTraceFunctionPointersFunc>(
+                base::GetFunctionPointerFromNativeLibrary(
+                    gles_library, "SetTraceFunctionPointers"));
+        if (set_trace_function_pointers) {
+          set_trace_function_pointers(&AngleGetTraceCategoryEnabledFlag,
+                                      &AngleAddTraceEvent);
+        }
+      }
+
       GLGetProcAddressProc get_proc_address =
           reinterpret_cast<GLGetProcAddressProc>(
               base::GetFunctionPointerFromNativeLibrary(