Allow Xcode to change paths to frameworks based on whether a device or simulator was selected.

R=caryclark@google.com
Review URL: https://codereview.appspot.com/6590068

git-svn-id: http://skia.googlecode.com/svn/trunk@5802 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gyp/SampleApp.gyp b/gyp/SampleApp.gyp
index c8b9ba7..3920152 100644
--- a/gyp/SampleApp.gyp
+++ b/gyp/SampleApp.gyp
@@ -247,15 +247,15 @@
           ],
           'link_settings': {
             'libraries': [
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/CoreFoundation.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/CoreGraphics.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/CoreText.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/UIKit.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/Foundation.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/QuartzCore.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/OpenGLES.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/ImageIO.framework',
-              '<(ios_sdk_dir)<(ios_sdk_version).sdk/System/Library/Frameworks/MobileCoreServices.framework',
+              '$(SDKROOT)/System/Library/Frameworks/CoreFoundation.framework',
+              '$(SDKROOT)/System/Library/Frameworks/CoreGraphics.framework',
+              '$(SDKROOT)/System/Library/Frameworks/CoreText.framework',
+              '$(SDKROOT)/System/Library/Frameworks/UIKit.framework',
+              '$(SDKROOT)/System/Library/Frameworks/Foundation.framework',
+              '$(SDKROOT)/System/Library/Frameworks/QuartzCore.framework',
+              '$(SDKROOT)/System/Library/Frameworks/OpenGLES.framework',
+              '$(SDKROOT)/System/Library/Frameworks/ImageIO.framework',
+              '$(SDKROOT)/System/Library/Frameworks/MobileCoreServices.framework',
             ],
           },
           'include_dirs' : [