Remove GP from drawstate, revision of invariant output for GP

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/c6bc58eded89b0c0a36b8e20e193c200f297a0da

Review URL: https://codereview.chromium.org/791743003
diff --git a/src/gpu/GrDistanceFieldTextContext.cpp b/src/gpu/GrDistanceFieldTextContext.cpp
index 641d0c1..d25757c 100755
--- a/src/gpu/GrDistanceFieldTextContext.cpp
+++ b/src/gpu/GrDistanceFieldTextContext.cpp
@@ -415,6 +415,7 @@
                                                                                    flags));
         } else {
             flags |= kColorAttr_DistanceFieldEffectFlag;
+            bool opaque = GrColorIsOpaque(color);
 #ifdef SK_GAMMA_APPLY_TO_A8
             U8CPU lum = SkColorSpaceLuminance::computeLuminance(fDeviceProperties.gamma(),
                                                                 filteredColor);
@@ -424,12 +425,14 @@
                                                                                 fGammaTexture,
                                                                                 gammaParams,
                                                                                 lum/255.f,
-                                                                                flags));
+                                                                                flags,
+                                                                                opaque));
 #else
             fCachedGeometryProcessor.reset(GrDistanceFieldNoGammaTextureEffect::Create(color,
                                                                                        fCurrTexture,
                                                                                        params,
-                                                                                       flags));
+                                                                                       flags,
+                                                                                       opaque));
 #endif
         }
         fEffectTextureUniqueID = textureUniqueID;
@@ -637,9 +640,6 @@
         }
         this->setupCoverageEffect(filteredColor);
 
-        // Effects could be stored with one of the cache objects (atlas?)
-        drawState.setGeometryProcessor(fCachedGeometryProcessor.get());
-
         // Set draw state
         if (fUseLCDText) {
             // TODO: move supportsRGBCoverage check to setupCoverageEffect and only add LCD
@@ -648,17 +648,15 @@
             if (!drawState.getXPFactory()->supportsRGBCoverage(0, kRGBA_GrColorComponentFlags)) {
                 SkDebugf("LCD Text will not draw correctly.\n");
             }
-            SkASSERT(!drawState.hasColorVertexAttribute());
+            SkASSERT(!fCachedGeometryProcessor->hasVertexColor());
         } else {
-            if (0xFF == GrColorUnpackA(fPaint.getColor())) {
-                drawState.setHint(GrDrawState::kVertexColorsAreOpaque_Hint, true);
-            }
             // We're using per-vertex color.
-            SkASSERT(drawState.hasColorVertexAttribute());
+            SkASSERT(fCachedGeometryProcessor->hasVertexColor());
         }
         int nGlyphs = fCurrVertex / kVerticesPerGlyph;
         fDrawTarget->setIndexSourceToBuffer(fContext->getQuadIndexBuffer());
         fDrawTarget->drawIndexedInstances(&drawState,
+                                          fCachedGeometryProcessor.get(),
                                           kTriangles_GrPrimitiveType,
                                           nGlyphs,
                                           kVerticesPerGlyph,