Remove unused and unimplemented abstract functions from GrRenderTarget

Remove unused and unimplemented abstract functions from GrRenderTarget.
The functions might cause confusion later.

BUG=skia:3388

Review URL: https://codereview.chromium.org/865603007
diff --git a/include/gpu/GrRenderTarget.h b/include/gpu/GrRenderTarget.h
index eaae49e..49cea63 100644
--- a/include/gpu/GrRenderTarget.h
+++ b/include/gpu/GrRenderTarget.h
@@ -30,20 +30,6 @@
 
     // GrRenderTarget
     /**
-     * If this RT is multisampled, this is the multisample buffer
-     * @return the 3D API's handle to this object (e.g. FBO ID in OpenGL)
-     */
-    virtual GrBackendObject getRenderTargetHandle() const = 0;
-
-    /**
-     * If this RT is multisampled, this is the buffer it is resolved to.
-     * Otherwise, same as getRenderTargetHandle().
-     * (In GL a separate FBO ID is used for the MSAA and resolved buffers)
-     * @return the 3D API's handle to this object (e.g. FBO ID in OpenGL)
-     */
-    virtual GrBackendObject getRenderTargetResolvedHandle() const = 0;
-
-    /**
      * @return true if the surface is multisampled, false otherwise
      */
     bool isMultisampled() const { return 0 != fDesc.fSampleCnt; }
diff --git a/src/gpu/gl/GrGLRenderTarget.h b/src/gpu/gl/GrGLRenderTarget.h
index ed1e2b3..4d08c14 100644
--- a/src/gpu/gl/GrGLRenderTarget.h
+++ b/src/gpu/gl/GrGLRenderTarget.h
@@ -42,8 +42,6 @@
     GrGLuint textureFBOID() const { return fTexFBOID; }
 
     // override of GrRenderTarget
-    GrBackendObject getRenderTargetHandle() const SK_OVERRIDE { return this->renderFBOID(); }
-    GrBackendObject getRenderTargetResolvedHandle() const SK_OVERRIDE { return this->textureFBOID(); }
     ResolveType getResolveType() const SK_OVERRIDE {
         if (!this->isMultisampled() ||
             fRTFBOID == fTexFBOID) {