Add some raster pipeline perspective asserts

I meant to add these when removing the guard, but since we landed without
a guard, might as well do it now.

A couple of things exposed by these asserts:

1) we need to also catch perspective in local matrices

2) we need to disallow burst mode with perspective

Also tweak the predicate to hasPerspective() instead of explicit mask
check.

Change-Id: I099e5125fca52dccffca77c60fc800bbdf539b53
Reviewed-on: https://skia-review.googlesource.com/22483
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
diff --git a/src/shaders/SkPictureShader.cpp b/src/shaders/SkPictureShader.cpp
index d80a7da..82439ae 100644
--- a/src/shaders/SkPictureShader.cpp
+++ b/src/shaders/SkPictureShader.cpp
@@ -265,7 +265,7 @@
     return tileShader;
 }
 
-bool SkPictureShader::isRasterPipelineOnly() const {
+bool SkPictureShader::onIsRasterPipelineOnly() const {
     return SkImageShader::IsRasterPipelineOnly(kN32_SkColorType, fTmx, fTmy);
 }