Update the SkDocument interface to allow for 1) abort won't emit pdf, 2) close can report success/f…

src/pdf/SkPDFShader.cpp

Index: src/pdf/SkPDFShader.cpp
diff --git a/src/pdf/SkPDFShader.cpp b/src/pdf/SkPDFShader.cpp
index 80ea2f2ce717feeac26c0e41a0714aafdf671370..70fb616a24f672cbf0b57603cf400defb69d0973 100644
--- a/src/pdf/SkPDFShader.cpp
+++ b/src/pdf/SkPDFShader.cpp
@@ -9,7 +9,6 @@
 
 #include "SkPDFShader.h"
 
-#include "SkCanvas.h"
 #include "SkData.h"
 #include "SkPDFCatalog.h"
 #include "SkPDFDevice.h"
@@ -870,6 +869,8 @@ SkPDFImageShader::SkPDFImageShader(SkPDFShader::State* state) : fState(state) {
     unflip.preScale(SK_Scalar1, -SK_Scalar1);
     SkISize size = SkISize::Make(SkScalarRound(deviceBounds.width()),
                                  SkScalarRound(deviceBounds.height()));
+    // TODO(edisonn): should we pass here the DCT encoder of the destination device?
+    // TODO(edisonn): NYI Perspective, use SkPDFDeviceFlattener.
     SkPDFDevice pattern(size, size, unflip);
     SkCanvas canvas(&pattern);