Add factory class for generating various flavors of GrTextContext.

This is the first pass of making Gr*TextContext more generic and easily
subclassed. The next stage will be making GrBitmapTextContext and
GrDistanceFieldTextContext more similar by moving the SkDraw loop into
each subclass.

BUG=skia:2018

Committed: http://code.google.com/p/skia/source/detail?r=13142

R=bsalomon@google.com, reed@google.com

Author: jvanverth@google.com

Review URL: https://codereview.chromium.org/144283002

git-svn-id: http://skia.googlecode.com/svn/trunk@13165 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrDistanceFieldTextContext.cpp b/src/gpu/GrDistanceFieldTextContext.cpp
index 95e773e..4c9631e 100755
--- a/src/gpu/GrDistanceFieldTextContext.cpp
+++ b/src/gpu/GrDistanceFieldTextContext.cpp
@@ -28,8 +28,7 @@
 GrDistanceFieldTextContext::GrDistanceFieldTextContext(GrContext* context,
                                                        const GrPaint& grPaint,
                                                        const SkPaint& skPaint)
-                                                     : GrTextContext(context, grPaint),
-                                                       fSkPaint(skPaint) {
+                                                     : GrTextContext(context, grPaint, skPaint) {
     fStrike = NULL;
 
     fCurrTexture = NULL;