Implemented transparent gradients

src/pdf/SkPDFDevice.cpp

Index: src/pdf/SkPDFDevice.cpp
diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index db0825af3a9f39d19dcc2a009690484cd32e8137..66c1aba8a901ce7fac5171966d62926b4fa3dcc8 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -1491,7 +1491,7 @@ void SkPDFDevice::drawFormXObjectWithClip(SkPDFFormXObject* xobject,
     this->drawPaint(draw, stockPaint);
     SkAutoTUnref<SkPDFFormXObject> maskFormXObject(createFormXObjectFromDevice());
     SkAutoTUnref<SkPDFGraphicState> sMaskGS(
-        SkPDFGraphicState::GetSMaskGraphicState(maskFormXObject, invertClip));
+        SkPDFGraphicState::GetSMaskGraphicState(maskFormXObject, invertClip, false));
 
     // Draw the xobject with the clip as a mask.
     ScopedContentEntry content(this, &fExistingClipStack, fExistingClipRegion,
@@ -1647,12 +1647,14 @@ void SkPDFDevice::finishContentEntry(const SkXfermode::Mode xfermode,
     if (xfermode == SkXfermode::kSrcIn_Mode ||
             xfermode == SkXfermode::kSrcOut_Mode) {
         sMaskGS.reset(SkPDFGraphicState::GetSMaskGraphicState(
-                dst, xfermode == SkXfermode::kSrcOut_Mode));
+                dst,
+                xfermode == SkXfermode::kSrcOut_Mode, true));
         fXObjectResources.push(srcFormXObject.get());
         srcFormXObject.get()->ref();
     } else {
         sMaskGS.reset(SkPDFGraphicState::GetSMaskGraphicState(
-                srcFormXObject.get(), xfermode == SkXfermode::kDstOut_Mode));
+                srcFormXObject.get(),
+                xfermode == SkXfermode::kDstOut_Mode, true));
         // dst already added to fXObjectResources in drawFormXObjectWithClip.
     }
     SkPDFUtils::ApplyGraphicState(addGraphicStateResource(sMaskGS.get()),