Put DirectWrite bitmap fix behind the SK_IGNORE_DWRITE_BITMAP_FIX flag.

src/ports/SkFontHost_win_dw.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkTypes.h"
 #undef GetGlyphIndices
 
@@ skipping 723 matching lines @@
 
     // GA is the matrix A with rotation removed.
     SkMatrix GA(G);
     GA.preConcat(A);
 
     // realTextSize is the actual device size we want (as opposed to the size the user requested).
     // gdiTextSize is the size we request when GDI compatible.
     // If the scale is negative, this means the matrix will do the flip anyway.
     SkScalar realTextSize = SkScalarAbs(GA.get(SkMatrix::kMScaleY));
     // Due to floating point math, the lower bits are suspect. Round carefully.
+#ifdef SK_IGNORE_DWRITE_BITMAP_FIX
+    SkScalar roundedTextSize = SkScalarRoundToScalar(realTextSize * 64.0f) / 64.0f;
+    SkScalar gdiTextSize = SkScalarFloorToScalar(roundedTextSize);
+#else
     SkScalar gdiTextSize = SkScalarRoundToScalar(realTextSize * 64.0f) / 64.0f;
+#endif
     if (gdiTextSize == 0) {
         gdiTextSize = SK_Scalar1;
     }
 
+#ifdef SK_IGNORE_DWRITE_BITMAP_FIX
+    bool hasBitmap = fRec.fFlags & SkScalerContext::kEmbeddedBitmapText_Flag &&
+                     hasBitmapStrike(typeface, SkScalarTruncToInt(gdiTextSize));
+    bool axisAligned = isAxisAligned(fRec);
+    bool isBiLevel = SkMask::kBW_Format == fRec.fMaskFormat || (hasBitmap && axisAligned);
+
+    if (isBiLevel) {
+#else
     bool bitmapRequested = SkToBool(fRec.fFlags & SkScalerContext::kEmbeddedBitmapText_Flag);
     bool hasBitmap = false;
     bool axisAlignedBitmap = false;
     if (bitmapRequested) {
         hasBitmap = hasBitmapStrike(typeface, SkScalarTruncToInt(gdiTextSize));
         axisAlignedBitmap = isAxisAligned(fRec);
     }
 
     // If the user requested aliased, do so with aliased compatible metrics.
     if (SkMask::kBW_Format == fRec.fMaskFormat) {
+#endif
         fTextSizeRender = gdiTextSize;
         fRenderingMode = DWRITE_RENDERING_MODE_ALIASED;
         fTextureType = DWRITE_TEXTURE_ALIASED_1x1;
         fTextSizeMeasure = gdiTextSize;
         fMeasuringMode = DWRITE_MEASURING_MODE_GDI_CLASSIC;
-
+#ifndef SK_IGNORE_DWRITE_BITMAP_FIX
     // If we can use a bitmap, use gdi classic rendering and measurement.
     // This will not always provide a bitmap, but matches expected behavior.
     } else if (hasBitmap && axisAlignedBitmap) {
         fTextSizeRender = gdiTextSize;
         fRenderingMode = DWRITE_RENDERING_MODE_CLEARTYPE_GDI_CLASSIC;
         fTextureType = DWRITE_TEXTURE_CLEARTYPE_3x1;
         fTextSizeMeasure = gdiTextSize;
         fMeasuringMode = DWRITE_MEASURING_MODE_GDI_CLASSIC;
-
+#endif
     // If rotated but the horizontal text could have used a bitmap,
     // render high quality rotated glyphs but measure using bitmap metrics.
     } else if (hasBitmap) {
         fTextSizeRender = gdiTextSize;
         fRenderingMode = DWRITE_RENDERING_MODE_CLEARTYPE_NATURAL_SYMMETRIC;
         fTextureType = DWRITE_TEXTURE_CLEARTYPE_3x1;
         fTextSizeMeasure = gdiTextSize;
         fMeasuringMode = DWRITE_MEASURING_MODE_GDI_CLASSIC;
 
     // The normal case is to use natural symmetric rendering and linear metrics.
@@ skipping 1235 matching lines @@
 }
 
 #include "SkFontMgr_indirect.h"
 SkFontMgr* SkFontMgr_New_DirectWriteRenderer(SkRemotableFontMgr* proxy) {
     SkAutoTUnref<SkFontMgr> impl(SkFontMgr_New_DirectWrite());
     if (impl.get() == NULL) {
         return NULL;
     }
     return SkNEW_ARGS(SkFontMgr_Indirect, (impl.get(), proxy));
 }