Add hooks for GL_EXT_debug_marker in gpu

src/gpu/gl/GrGpuGL.cpp

Index: src/gpu/gl/GrGpuGL.cpp
diff --git a/src/gpu/gl/GrGpuGL.cpp b/src/gpu/gl/GrGpuGL.cpp
index ec9c8d6fab7e3ea5bebf77280966d68fe1b7851f..5fb268863b25a256113631ca3f06705e0024116a 100644
--- a/src/gpu/gl/GrGpuGL.cpp
+++ b/src/gpu/gl/GrGpuGL.cpp
@@ -117,14 +117,12 @@ GrGpuGL::GrGpuGL(const GrGLContext& ctx, GrContext* context)
     , fGLContext(ctx) {
 
     SkASSERT(ctx.isInitialized());
-
     fCaps.reset(SkRef(ctx.caps()));
 
     fHWBoundTextures.reset(this->glCaps().maxFragmentTextureUnits());
     fHWTexGenSettings.reset(this->glCaps().maxFixedFunctionTextureCoords());
 
     GrGLClearErr(fGLContext.interface());
-
     if (gPrintStartupSpew) {
         const GrGLubyte* vendor;
         const GrGLubyte* renderer;
@@ -2663,6 +2661,23 @@ bool GrGpuGL::onCanCopySurface(GrSurface* dst,
     return INHERITED::onCanCopySurface(dst, src, srcRect, dstPoint);
 }
 
+void GrGpuGL::onInstantGpuTraceEvent(const char* marker) {
+    if (this->caps()->gpuTracingSupport()) {
+        // GL_CALL(InsertEventMarker(0, marker));
+    }
+}
+
+void GrGpuGL::onPushGpuTraceEvent(const char* marker) {
+    if (this->caps()->gpuTracingSupport()) {
+        // GL_CALL(PushGroupMarker(0, marker));
+    }
+}
+
+void GrGpuGL::onPopGpuTraceEvent() {
+    if (this->caps()->gpuTracingSupport()) {
+        // GL_CALL(PopGroupMarker());
+    }
+}
 
 ///////////////////////////////////////////////////////////////////////////////