fix build error in chromium

NOTREECHECKS=true
NOTRY=true
R=fmalita@google.com, jvanverth@google.com, fmalita@chromium.org
TBR=fmalita@google.com

Author: halcanary@google.com

Review URL: https://codereview.chromium.org/195223004

git-svn-id: http://skia.googlecode.com/svn/trunk@13749 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/effects/GrDistanceFieldTextureEffect.cpp b/src/gpu/effects/GrDistanceFieldTextureEffect.cpp
index 2998a54..9159a70 100755
--- a/src/gpu/effects/GrDistanceFieldTextureEffect.cpp
+++ b/src/gpu/effects/GrDistanceFieldTextureEffect.cpp
@@ -56,7 +56,7 @@
                                        fsCoordName.c_str(),
                                        kVec2f_GrSLType);
         builder->fsCodeAppend(";\n");
-        builder->fsCodeAppend("\tfloat distance = "MULTIPLIER"*(texColor.r - "THRESHOLD");\n");
+        builder->fsCodeAppend("\tfloat distance = " MULTIPLIER "*(texColor.r - " THRESHOLD ");\n");
 
         // we adjust for the effect of the transformation on the distance by using
         // the length of the gradient of the texture coordinates. We use st coordinates