Clean up EGL thread state at thread exit in nanobench and DM

src/gpu/gl/iOS/SkCreatePlatformGLContext_iOS.mm

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gl/SkGLContext.h"
 #import <OpenGLES/EAGL.h>
@@ skipping 86 matching lines @@
     if (kGL_GrGLStandard == forcedGpuAPI) {
         return NULL;
     }
     IOSGLContext* ctx = new IOSGLContext;
     if (!ctx->isValid()) {
         delete ctx;
         return NULL;
     }
     return ctx;
 }
+
+void SkReleasePlatformGLAPIsInThread() {
+}