Some fixes around GrContext::abandonContext:

src/gpu/gl/debug/GrGLCreateDebugInterface.cpp

Index: src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
diff --git a/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp b/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
index 788179cd845d9082d46d8570525e25cf55d0a0d1..0279427d3be4849689c4e6ac867d63f7878483eb 100644
--- a/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
+++ b/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
@@ -796,6 +796,10 @@ public:
         fWrapped.reset(interface);
     }
 
+    virtual void abandon() const SK_OVERRIDE {
+        GrDebugGL::abandon();
+    }
+
     // TODO: there are some issues w/ wrapping another GL interface inside the
     // debug interface:
     //      Since none of the "gl" methods are member functions they don't get