Update iOS deployment target to 7.0

iOS 6 will no longer be supported.

Replaces deprecated sizeWithFont: with sizeWithAttributes: (adding a
ceilf since according to the internet, the former rounds up, and the
latter does not) to fix compilation.

BUG=402921

Review URL: https://codereview.chromium.org/463333002

git-svn-id: http://src.chromium.org/svn/trunk/src/build@289403 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -1618,7 +1618,7 @@
         # not using the "current" SDK.
         'ios_sdk%': '',
         'ios_sdk_path%': '',
-        'ios_deployment_target%': '6.0',
+        'ios_deployment_target%': '7.0',
 
         'conditions': [
           # ios_product_name is set to the name of the .app bundle as it should
@@ -5020,6 +5020,10 @@
                   'CLANG_CXX_LIBRARY': 'libc++',  # -stdlib=libc++
                 }]
               ],
+            }, {
+              # The default for deployment target of 7.0+ is libc++, so force
+              # the old behavior unless libc++ is enabled.
+              'CLANG_CXX_LIBRARY': 'libstdc++',  # -stdlib=libstdc++
             }],
           ],
         },