Change GLGetProcAddress typedef to function returning function pointer

ui/gl/gl_implementation.h

Index: ui/gl/gl_implementation.h
diff --git a/ui/gl/gl_implementation.h b/ui/gl/gl_implementation.h
index 3566f368b4c3310f18d5853637cf71653575dab6..dc425076a098828531057b264302407f58bbee21 100644
--- a/ui/gl/gl_implementation.h
+++ b/ui/gl/gl_implementation.h
@@ -35,10 +35,11 @@ struct GL_EXPORT GLWindowSystemBindingInfo {
   bool direct_rendering;
 };
 
+using GLFunctionPointerType = void (*)();

[Ken Russell (switch to Gerrit), 2016/12/21 16:45:17]

Is it OK that this "using" statement doesn't include the calling convention
WINAPI on Windows platforms? Given that everything compiles and passes tests I
assume it is, but the GL headers all use that specifier on the function pointers
they define.

 #if defined(OS_WIN)
-typedef void* (WINAPI *GLGetProcAddressProc)(const char* name);
+typedef GLFunctionPointerType(WINAPI* GLGetProcAddressProc)(const char* name);
 #else
-typedef void* (*GLGetProcAddressProc)(const char* name);
+typedef GLFunctionPointerType (*GLGetProcAddressProc)(const char* name);
 #endif
 
 // Initialize stub methods for drawing operations in the GL bindings. The
@@ -99,7 +100,7 @@ GL_EXPORT void SetGLGetProcAddressProc(GLGetProcAddressProc proc);
 // and when querying functions from the EGL library supplied by Android, it may
 // return a function that prints a log message about the function being
 // unsupported.
-GL_EXPORT void* GetGLProcAddress(const char* name);
+GL_EXPORT GLFunctionPointerType GetGLProcAddress(const char* name);
 
 // Helper for fetching the OpenGL extensions from the current context.
 // This helper abstracts over differences between the desktop OpenGL