Remove GrStagedProcessor, remove the word Stage as it applies to FPs

Committed: https://skia.googlesource.com/skia/+/24243446cdf7b7e4e132c2a0c387c7723777e0c7

Review URL: https://codereview.chromium.org/1307223004
diff --git a/gm/constcolorprocessor.cpp b/gm/constcolorprocessor.cpp
index 2287af4..f5d7853 100644
--- a/gm/constcolorprocessor.cpp
+++ b/gm/constcolorprocessor.cpp
@@ -113,7 +113,7 @@
 
                     GrClip clip;
                     GrPipelineBuilder pipelineBuilder(grPaint, rt, clip);
-                    pipelineBuilder.addColorProcessor(fp);
+                    pipelineBuilder.addColorFragmentProcessor(fp);
 
                     tt.target()->drawNonAARect(pipelineBuilder,
                                                grPaint.getColor(),