fix typo in matrix proc index computation, where we were always taking the
perspective case when affine would have been enough (and lots faster).



git-svn-id: http://skia.googlecode.com/svn/trunk@323 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/core/SkBitmapProcState_matrixProcs.cpp b/src/core/SkBitmapProcState_matrixProcs.cpp
index bd924ca..67b57c4 100644
--- a/src/core/SkBitmapProcState_matrixProcs.cpp
+++ b/src/core/SkBitmapProcState_matrixProcs.cpp
@@ -399,7 +399,7 @@
     if (fInvType & SkMatrix::kPerspective_Mask) {
         index += 4;
     } else if (fInvType & SkMatrix::kAffine_Mask) {
-        index += 4;
+        index += 2;
     }
     
     if (SkShader::kClamp_TileMode == fTileModeX &&