Use correct gradient calculation for rotated distance fields.

src/gpu/batches/GrAtlasTextBatch.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrAtlasTextBatch.h"
 
 #include "GrBatchFlushState.h"
@@ skipping 243 matching lines @@
 
 // TODO just use class params
 // TODO trying to figure out why lcd is so whack
 GrGeometryProcessor* GrAtlasTextBatch::setupDfProcessor(const SkMatrix& viewMatrix,
                                                         SkColor filteredColor,
                                                         GrColor color, GrTexture* texture) const {
     GrTextureParams params(SkShader::kClamp_TileMode, GrTextureParams::kBilerp_FilterMode);
     bool isLCD = this->isLCD();
     // set up any flags
     uint32_t flags = viewMatrix.isSimilarity() ? kSimilarity_DistanceFieldEffectFlag : 0;
+    flags |= viewMatrix.isScaleTranslate() ? kScaleOnly_DistanceFieldEffectFlag : 0;
 
     // see if we need to create a new effect
     if (isLCD) {
         flags |= kUseLCD_DistanceFieldEffectFlag;
-        flags |= viewMatrix.rectStaysRect() ? kRectToRect_DistanceFieldEffectFlag : 0;
         flags |= fUseBGR ? kBGR_DistanceFieldEffectFlag : 0;
 
         GrColor colorNoPreMul = skcolor_to_grcolor_nopremultiply(filteredColor);
 
         float redCorrection =
             (*fDistanceAdjustTable)[GrColorUnpackR(colorNoPreMul) >> kDistanceAdjustLumShift];
         float greenCorrection =
             (*fDistanceAdjustTable)[GrColorUnpackG(colorNoPreMul) >> kDistanceAdjustLumShift];
         float blueCorrection =
             (*fDistanceAdjustTable)[GrColorUnpackB(colorNoPreMul) >> kDistanceAdjustLumShift];
@@ skipping 29 matching lines @@
                                                     this->usesLocalCoords());
 #endif
     }
 
 }
 
 void GrBlobRegenHelper::flush() {
     fBatch->flush(fTarget, fFlushInfo);
     fTarget->initDraw(fGP, fBatch->pipeline());
 }