Added registerChild; transforms, textures, glKey automatically handled.

BUG=skia:

Review URL: https://codereview.chromium.org/1266633003
diff --git a/src/gpu/effects/GrSimpleTextureEffect.cpp b/src/gpu/effects/GrSimpleTextureEffect.cpp
index 066ccf7..e3389bb 100644
--- a/src/gpu/effects/GrSimpleTextureEffect.cpp
+++ b/src/gpu/effects/GrSimpleTextureEffect.cpp
@@ -37,7 +37,7 @@
     this->updateInvariantOutputForModulation(inout);
 }
 
-void GrSimpleTextureEffect::getGLProcessorKey(const GrGLSLCaps& caps,
+void GrSimpleTextureEffect::onGetGLProcessorKey(const GrGLSLCaps& caps,
                                               GrProcessorKeyBuilder* b) const {
     GrGLSimpleTextureEffect::GenKey(*this, caps, b);
 }