Fix a number of issues with iOS build.

gyp/SampleApp.gyp

 #
 {
   'variables': {
     #manually set sample_pdf_file_viewer to 1 to have the PdfViewer in SampleApp
     'sample_pdf_file_viewer%': 0,
   },
   'targets': [
     {
       'target_name': 'SampleApp',
       'type': 'executable',
@@ skipping 218 matching lines @@
             '../experimental/iOSSampleApp/iPad/MainWindow_iPad.xib',
 
             # iPhone
             '../experimental/iOSSampleApp/iPhone/AppDelegate_iPhone.mm',
             '../experimental/iOSSampleApp/iPhone/SkUINavigationController.mm',
             '../experimental/iOSSampleApp/iPhone/MainWindow_iPhone.xib',
 
             '../src/views/ios/SkOSWindow_iOS.mm',
             '../src/utils/ios/SkImageDecoder_iOS.mm',
             '../src/utils/ios/SkStream_NSData.mm',
-            '../src/utils/ios/SkOSFile_iOS.mm',
+            # Not fully implemented yet
+            # '../src/utils/ios/SkOSFile_iOS.mm',
 
             '../src/utils/mac/SkCreateCGImageRef.cpp',
             '../experimental/iOSSampleApp/SkiOSSampleApp-Debug.xcconfig',
             '../experimental/iOSSampleApp/SkiOSSampleApp-Release.xcconfig',
           ],
           'link_settings': {
             'libraries': [
               '$(SDKROOT)/System/Library/Frameworks/CoreFoundation.framework',
               '$(SDKROOT)/System/Library/Frameworks/CoreGraphics.framework',
               '$(SDKROOT)/System/Library/Frameworks/CoreText.framework',
@@ skipping 46 matching lines @@
         }],
       ],
       'msvs_settings': {
         'VCLinkerTool': {
           'SubSystem': '2',
         },
       },
     },
   ],
 }