Stop discarding in frag shader when coverage is zero and stencil writes are enabled

src/gpu/gl/GrGLProgramDesc.h

Index: src/gpu/gl/GrGLProgramDesc.h
diff --git a/src/gpu/gl/GrGLProgramDesc.h b/src/gpu/gl/GrGLProgramDesc.h
index ec3f0979068307b179a7dab07b6a32f093dfc62b..9116fdf66ff5f1df7ada6cf7f56e1cf69fa9b282 100644
--- a/src/gpu/gl/GrGLProgramDesc.h
+++ b/src/gpu/gl/GrGLProgramDesc.h
@@ -151,9 +151,6 @@ private:
                                                         // effects that read the fragment position.
                                                         // Otherwise, 0.
 
-        // should the FS discard if the coverage is zero (to avoid stencil manipulation)
-        SkBool8                     fDiscardIfZeroCoverage;
-
         ColorInput                  fColorInput : 8;
         ColorInput                  fCoverageInput : 8;
         CoverageOutput              fCoverageOutput : 8;