Only use fake gamma with linear devices.

src/gpu/text/GrStencilAndCoverTextContext.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrStencilAndCoverTextContext.h"
 #include "GrAtlasTextContext.h"
 #include "GrDrawContext.h"
@@ skipping 611 matching lines @@
         }
 
         fallbackTextContext->drawTextBlob(ctx, dc, pipelineBuilder->clip(), fallbackSkPaint,
                                           viewMatrix, props, fFallbackTextBlob, x, y, nullptr,
                                           clipBounds);
     }
 }
 
 SkGlyphCache* GrStencilAndCoverTextContext::TextRun::getGlyphCache() const {
     if (!fDetachedGlyphCache) {
-        fDetachedGlyphCache = fFont.detachCache(nullptr, nullptr, true /*ignoreGamma*/);
+        fDetachedGlyphCache = fFont.detachCache(nullptr, SkPaint::FakeGamma::Off, nullptr);
     }
     return fDetachedGlyphCache;
 }
 
 
 void GrStencilAndCoverTextContext::TextRun::releaseGlyphCache() const {
     if (fDetachedGlyphCache) {
         SkGlyphCache::AttachCache(fDetachedGlyphCache);
         fDetachedGlyphCache = nullptr;
     }
@@ skipping 54 matching lines @@
 }
 
 const SkTextBlob* GrStencilAndCoverTextContext::FallbackBlobBuilder::buildIfNeeded(int *count) {
     *count = fCount;
     if (fCount) {
         this->flush();
         return fBuilder->build();
     }
     return nullptr;
 }