SkPDF: Re-use Jpeg Image Shaders

Also, de-dup shader better.

  - SkBitmapKeyFromImage function factors out image de-dup code.
  - SkPDFUtils::ToBitmap funtion factors out to-bitmap code
  - make_image_shader function now takes Image rather than Bitmap.

All tests render the same.  Some are significantly smaller PDFs.

Change-Id: Id8dd36b31c8e573f44a5e9f6058d5a1d622b6385
Reviewed-on: https://skia-review.googlesource.com/24081
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Hal Canary <halcanary@google.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/pdf/SkKeyedImage.h b/src/pdf/SkKeyedImage.h
index f74ec5c170..f489e576cd 100644
--- a/src/pdf/SkKeyedImage.h
+++ b/src/pdf/SkKeyedImage.h
@@ -37,4 +37,10 @@ private:
     sk_sp<SkImage> fImage;
     SkBitmapKey fKey = {{0, 0, 0, 0}, 0};
 };
+
+/**
+ *  Given an Image, return the Bitmap Key that corresponds to it.  If the Image
+ *  wraps a Bitmap, use that Bitmap's key.
+ */
+SkBitmapKey SkBitmapKeyFromImage(const SkImage*);
 #endif  // SkKeyedImage_DEFINED