disable optimization in Mac debug build



git-svn-id: http://skia.googlecode.com/svn/trunk/gyp@1994 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/common.gypi b/common.gypi
index 6bba0f2..f1f1e97 100644
--- a/common.gypi
+++ b/common.gypi
@@ -138,10 +138,9 @@
           ],
           'configurations': {
             'Debug': {
-              'cflags': ['-g']
-            },
-            'Release': {
-              'cflags': ['-O2']
+              'xcode_settings': {
+                'GCC_OPTIMIZATION_LEVEL': '0',
+              },
             },
           },
           'xcode_settings': {
@@ -157,10 +156,9 @@
           ],
           'configurations': {
             'Debug': {
-              'cflags': ['-g']
-            },
-            'Release': {
-              'cflags': ['-O2']
+              'xcode_settings': {
+                'GCC_OPTIMIZATION_LEVEL': '0',
+              },
             },
           },
           'xcode_settings': {