Rename some processor functions from GL to GLSL

TBR=bsalomon@google.com

BUG=skia:

Review URL: https://codereview.chromium.org/1443743002
diff --git a/src/gpu/effects/GrTextureDomain.h b/src/gpu/effects/GrTextureDomain.h
index a215def..aa1db00 100644
--- a/src/gpu/effects/GrTextureDomain.h
+++ b/src/gpu/effects/GrTextureDomain.h
@@ -187,9 +187,9 @@
                           GrTextureParams::FilterMode,
                           GrCoordSet);
 
-    GrGLSLFragmentProcessor* onCreateGLInstance() const override;
+    GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
 
-    void onGetGLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
+    void onGetGLSLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
 
     bool onIsEqual(const GrFragmentProcessor&) const override;