Move ViewMatrix off of drawstate

BUG=skia:

Review URL: https://codereview.chromium.org/815553003
diff --git a/src/gpu/GrGeometryProcessor.cpp b/src/gpu/GrGeometryProcessor.cpp
index d47f687..01ea85a 100644
--- a/src/gpu/GrGeometryProcessor.cpp
+++ b/src/gpu/GrGeometryProcessor.cpp
@@ -119,8 +119,10 @@
     typedef GrGLGeometryProcessor INHERITED;
 };
 
-GrPathProcessor::GrPathProcessor(GrColor color, const SkMatrix& localMatrix)
-    : INHERITED(localMatrix)
+GrPathProcessor::GrPathProcessor(GrColor color,
+                                 const SkMatrix& viewMatrix,
+                                 const SkMatrix& localMatrix)
+    : INHERITED(viewMatrix, localMatrix)
     , fColor(color) {
     this->initClassID<GrPathProcessor>();
 }
@@ -155,6 +157,10 @@
         return false;
     }
 
+    if (!this->viewMatrix().cheapEqualTo(that.viewMatrix())) {
+        return false;
+    }
+
     const PathBatchTracker& mine = m.cast<PathBatchTracker>();
     const PathBatchTracker& theirs = t.cast<PathBatchTracker>();
     return CanCombineLocalMatrices(*this, mine.fUsesLocalCoords,