Use high precision vertex attributes.

src/gpu/effects/GrDistanceFieldGeoProc.cpp

Index: src/gpu/effects/GrDistanceFieldGeoProc.cpp
diff --git a/src/gpu/effects/GrDistanceFieldGeoProc.cpp b/src/gpu/effects/GrDistanceFieldGeoProc.cpp
index 1e454a00010b8856ffbf17e009923551e33bf35a..92fe0a4ab7c221f69e4700b188a2703ceed9fa58 100755
--- a/src/gpu/effects/GrDistanceFieldGeoProc.cpp
+++ b/src/gpu/effects/GrDistanceFieldGeoProc.cpp
@@ -205,7 +205,8 @@ GrDistanceFieldA8TextGeoProc::GrDistanceFieldA8TextGeoProc(GrColor color,
     , fUsesLocalCoords(usesLocalCoords) {
     SkASSERT(!(flags & ~kNonLCD_DistanceFieldEffectMask));
     this->initClassID<GrDistanceFieldA8TextGeoProc>();
-    fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType));
+    fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType,
+                                                   kHigh_GrSLPrecision));
     if (flags & kColorAttr_DistanceFieldEffectFlag) {
         fInColor = &this->addVertexAttrib(Attribute("inColor", kVec4ub_GrVertexAttribType));
     }
@@ -420,7 +421,8 @@ GrDistanceFieldPathGeoProc::GrDistanceFieldPathGeoProc(
     , fUsesLocalCoords(usesLocalCoords) {
     SkASSERT(!(flags & ~kNonLCD_DistanceFieldEffectMask));
     this->initClassID<GrDistanceFieldPathGeoProc>();
-    fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType));
+    fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType,
+                                                   kHigh_GrSLPrecision));
     if (flags & kColorAttr_DistanceFieldEffectFlag) {
         fInColor = &this->addVertexAttrib(Attribute("inColor", kVec4ub_GrVertexAttribType));
     }
@@ -674,7 +676,8 @@ GrDistanceFieldLCDTextGeoProc::GrDistanceFieldLCDTextGeoProc(
     , fUsesLocalCoords(usesLocalCoords) {
     SkASSERT(!(flags & ~kLCD_DistanceFieldEffectMask) && (flags & kUseLCD_DistanceFieldEffectFlag));
     this->initClassID<GrDistanceFieldLCDTextGeoProc>();
-    fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType));
+    fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType,
+                                                   kHigh_GrSLPrecision));
     fInTextureCoords = &this->addVertexAttrib(Attribute("inTextureCoords",
                                                         kVec2s_GrVertexAttribType));
     this->addTextureAccess(&fTextureAccess);