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

src/pdf/SkPDFShader.cpp

Index: src/pdf/SkPDFShader.cpp
===================================================================
--- src/pdf/SkPDFShader.cpp	(revision 11092)
+++ src/pdf/SkPDFShader.cpp	(working copy)
@@ -55,6 +55,10 @@
  */
 static void interpolateColorCode(SkScalar range, SkScalar* curColor,
                                  SkScalar* prevColor, SkString* result) {
+    if (range == SkIntToScalar(0)) {

[vandebo (ex-Chrome), 2013/09/12 21:37:05]

This should go to a different CL.

You can't just return (that violates the interface of this function).  Based on
the comment, I think you need to result->append("pop").

[edisonn, 2013/09/17 15:14:23]

Done.

+        return;
+    }
+
     static const int kColorComponents = 3;
 
     // Figure out how to scale each color component.
@@ -578,6 +582,13 @@
 SkPDFObject* SkPDFShader::GetPDFShader(const SkShader& shader,
                                        const SkMatrix& matrix,
                                        const SkIRect& surfaceBBox) {
+    if (matrix.hasPerspective() || shader.getLocalMatrix().hasPerspective()) {
+        NOT_IMPLEMENTED(true, false);  // just report that PDF does not supports perspective
+                                       // TODO(edisonn): update the shape when possible
+                                       // or dump in an image otherwise
+        return NULL;
+    }
+
     SkAutoMutexAcquire lock(CanonicalShadersMutex());
     return GetPDFShaderByState(
             SkNEW_ARGS(State, (shader, matrix, surfaceBBox)));