Change GLGetProcAddress typedef to function returning function pointer

ui/gl/gl_implementation.cc

Index: ui/gl/gl_implementation.cc
diff --git a/ui/gl/gl_implementation.cc b/ui/gl/gl_implementation.cc
index c0c531746e5852ba9d6ec670dd3b0ba033213ed6..0b88b820f71b968a7eb2780c021d156822fa54bd 100644
--- a/ui/gl/gl_implementation.cc
+++ b/ui/gl/gl_implementation.cc
@@ -123,19 +123,19 @@ void SetGLGetProcAddressProc(GLGetProcAddressProc proc) {
   g_get_proc_address = proc;
 }
 
-void* GetGLProcAddress(const char* name) {
+GLFunctionPointerType GetGLProcAddress(const char* name) {
   DCHECK(g_gl_implementation != kGLImplementationNone);
 
   if (g_libraries) {
     for (size_t i = 0; i < g_libraries->size(); ++i) {
-      void* proc = base::GetFunctionPointerFromNativeLibrary((*g_libraries)[i],
-                                                             name);
+      GLFunctionPointerType proc = reinterpret_cast<GLFunctionPointerType>(
+          base::GetFunctionPointerFromNativeLibrary((*g_libraries)[i], name));
       if (proc)
         return proc;
     }
   }
   if (g_get_proc_address) {
-    void* proc = g_get_proc_address(name);
+    GLFunctionPointerType proc = g_get_proc_address(name);
     if (proc)
       return proc;
   }