Use const where possible for drawing parameters

They should never be modified by a Renderer, only read and copied.

Change-Id: I9d8d55dca19115ee9dfeb2bb3f092ba2fb327cd4
diff --git a/libs/hwui/PathTessellator.h b/libs/hwui/PathTessellator.h
index 24f20bc..e43b101 100644
--- a/libs/hwui/PathTessellator.h
+++ b/libs/hwui/PathTessellator.h
@@ -34,10 +34,10 @@
     static void tessellatePath(const SkPath& path, const SkPaint* paint,
             const mat4& transform, VertexBuffer& vertexBuffer);
 
-    static void tessellatePoints(const float* points, int count, SkPaint* paint,
+    static void tessellatePoints(const float* points, int count, const SkPaint* paint,
             const mat4& transform, SkRect& bounds, VertexBuffer& vertexBuffer);
 
-    static void tessellateLines(const float* points, int count, SkPaint* paint,
+    static void tessellateLines(const float* points, int count, const SkPaint* paint,
             const mat4& transform, SkRect& bounds, VertexBuffer& vertexBuffer);
 
 private: