Add hooks for GL_EXT_debug_marker in gpu

src/gpu/gl/GrGLCaps.cpp

 /*
  * 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 "GrGLCaps.h"
 #include "GrGLContext.h"
@@ skipping 294 matching lines @@
 
     GR_GL_GetIntegerv(gli, GR_GL_MAX_TEXTURE_SIZE, &fMaxTextureSize);
     GR_GL_GetIntegerv(gli, GR_GL_MAX_RENDERBUFFER_SIZE, &fMaxRenderTargetSize);
     // Our render targets are always created with textures as the color
     // attachment, hence this min:
     fMaxRenderTargetSize = GrMin(fMaxTextureSize, fMaxRenderTargetSize);
 
     fPathRenderingSupport = ctxInfo.hasExtension("GL_NV_path_rendering");
     SkASSERT(!fPathRenderingSupport || fFixedFunctionSupport);
 
+    fGpuTracingSupport = ctxInfo.hasExtension("GL_EXT_debug_marker");
+
     fDstReadInShaderSupport = kNone_FBFetchType != fFBFetchType;
 
     // Disable scratch texture reuse on Mali and Adreno devices
     fReuseScratchTextures = kARM_GrGLVendor != ctxInfo.vendor() &&
                             kQualcomm_GrGLVendor != ctxInfo.vendor();
 
     // Enable supported shader-related caps
     if (kGL_GrGLStandard == standard) {
         fDualSourceBlendingSupport = ctxInfo.version() >= GR_GL_VER(3,3) ||
                                      ctxInfo.hasExtension("GL_ARB_blend_func_extended");
@@ skipping 329 matching lines @@
     r.appendf("Two Format Limit: %s\n", (fTwoFormatLimit ? "YES": "NO"));
     r.appendf("Fragment coord conventions support: %s\n",
              (fFragCoordsConventionSupport ? "YES": "NO"));
     r.appendf("Vertex array object support: %s\n", (fVertexArrayObjectSupport ? "YES": "NO"));
     r.appendf("Use non-VBO for dynamic data: %s\n",
              (fUseNonVBOVertexAndIndexDynamicData ? "YES" : "NO"));
     r.appendf("Discard FrameBuffer support: %s\n", (fDiscardFBSupport ? "YES" : "NO"));
     r.appendf("Full screen clear is free: %s\n", (fFullClearIsFree ? "YES" : "NO"));
     return r;
 }