Remove usage of FOR_EACH_OBSERVER macro in gpu

gpu/command_buffer/service/shader_translator.cc

Index: gpu/command_buffer/service/shader_translator.cc
diff --git a/gpu/command_buffer/service/shader_translator.cc b/gpu/command_buffer/service/shader_translator.cc
index d24a90d35b793d2bada56f476431f82172d4897a..60b6d63692a9ec1d28a909478671f1a9482b2121 100644
--- a/gpu/command_buffer/service/shader_translator.cc
+++ b/gpu/command_buffer/service/shader_translator.cc
@@ -276,9 +276,8 @@ void ShaderTranslator::RemoveDestructionObserver(
 }
 
 ShaderTranslator::~ShaderTranslator() {
-  FOR_EACH_OBSERVER(DestructionObserver,
-                    destruction_observers_,
-                    OnDestruct(this));
+  for (auto& observer : destruction_observers_)
+    observer.OnDestruct(this);
 
   if (compiler_ != NULL)
     ShDestruct(compiler_);