pdfviewer: fix build break in windows (wrong return type on function)

experimental/PdfViewer/SkPdfGraphicsState.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPdfGraphicsState_DEFINED
 #define SkPdfGraphicsState_DEFINED
 
@@ skipping 40 matching lines @@
             Rec* next = rec->fNext;
             delete rec;
             rec = next;
         }
     }
 
     int count() const { return fLocalCount; }
     int depth() const { return fLocalCount; }
     bool empty() const { return fLocalCount == 0; }
 
-    bool nests() {
+    int nests() {
         return fNestingLevel;
     }
 
     void nest() {
         // We are are past max nesting levels, we will still continue to work, but we might fail
         // to properly ignore errors. Ideally it should only mean poor rendering in exceptional
         // cases
         if (fNestingLevel >= 0 && fNestingLevel < MAX_NESTING) {
             fNestings[fNestingLevel] = fLocalCount;
             fLocalCount = 0;
@@ skipping 433 matching lines @@
     SkPdfGraphicsState              fGraphicsState;
     SkPdfNativeDoc*                 fPdfDoc;
     SkPdfAllocator*                 fTmpPageAllocator;
     SkMatrix                        fOriginalMatrix;
 
     SkPdfContext(SkPdfNativeDoc* doc);
     ~SkPdfContext();
 };
 
 #endif  // SkPdfGraphicsState_DEFINED