pdf: report NYI features, and fail gracefully when something is not supported in pdf.

src/pdf/SkPDFDevice.cpp

Index: src/pdf/SkPDFDevice.cpp
===================================================================
--- src/pdf/SkPDFDevice.cpp	(revision 11353)
+++ src/pdf/SkPDFDevice.cpp	(working copy)
@@ -632,6 +632,16 @@
     void init(const SkClipStack* clipStack, const SkRegion& clipRegion,
               const SkMatrix& matrix, const SkPaint& paint, bool hasText) {
         fDstFormXObject = NULL;
+        if (matrix.hasPerspective() ||
+                (paint.getShader() &&
+                 paint.getShader()->getLocalMatrix().hasPerspective())) {
+            // Just report that PDF does not supports perspective
+            // TODO(edisonn): update the shape when possible
+            // or dump in an image otherwise
+            NOT_IMPLEMENTED(true, false);
+            return;
+        }
+
         if (paint.getXfermode()) {
             paint.getXfermode()->asMode(&fXfermode);
         }
@@ -679,6 +689,11 @@
       fLastMarginContentEntry(NULL),
       fClipStack(NULL),
       fEncoder(NULL) {
+    // just report that PDF does not supports perspective
+    // TODO(edisonn): update the shape when possible
+    // or dump in an image otherwise
+    NOT_IMPLEMENTED(initialTransform.hasPerspective(), true);
+
     // Skia generally uses the top left as the origin but PDF natively has the
     // origin at the bottom left. This matrix corrects for that.  But that only
     // needs to be done once, we don't do it when layering.
@@ -915,6 +930,7 @@
             origPath.transform(*prePathMatrix, pathPtr);
         } else {
             if (!matrix.preConcat(*prePathMatrix)) {
+                // TODO(edisonn): report somehow why we failed?
                 return;
             }
         }