pdfviewer: when q start, and an operator is called, it should not be able to see operands before q.…

experimental/PdfViewer/pdfparser/native/SkPdfNativeDoc.cpp

Index: experimental/PdfViewer/pdfparser/native/SkPdfNativeDoc.cpp
===================================================================
--- experimental/PdfViewer/pdfparser/native/SkPdfNativeDoc.cpp	(revision 10854)
+++ experimental/PdfViewer/pdfparser/native/SkPdfNativeDoc.cpp	(working copy)
@@ -358,6 +358,7 @@
     fObjects[id].fOffset = offset;
     fObjects[id].fObj = NULL;
     fObjects[id].fResolvedReference = NULL;
+    fObjects[id].fIsReferenceResolved = false;
 }
 
 SkPdfNativeObject* SkPdfNativeDoc::readObject(int id/*, int expectedGeneration*/) {
@@ -546,15 +547,22 @@
             return NULL;
         }
 
-        if (fObjects[id].fResolvedReference != NULL) {
+        if (fObjects[id].fIsReferenceResolved) {
 
 #ifdef PDF_TRACE
             printf("\nresolve(%s) = %s\n", ref->toString(0).c_str(), fObjects[id].fResolvedReference->toString(0, ref->toString().size() + 13).c_str());
 #endif
 
+            // TODO(edisonn): for known good documents, assert here THAT THE REFERENCE IS NOT null
             return fObjects[id].fResolvedReference;
         }
 
+        // TODO(edisonn): there are pdfs in the crashing suite that cause a stack overflow here unless we check for resolved reference on next line
+        // determine if the pdf is corrupted, or we have a bug here
+
+        // avoids recursive calls
+        fObjects[id].fIsReferenceResolved = true;
+
         if (fObjects[id].fObj == NULL) {
             fObjects[id].fObj = readObject(id);
         }