Build in C++11 mode on Unix-like bots.

gyp/common_conditions.gypi

Index: gyp/common_conditions.gypi
diff --git a/gyp/common_conditions.gypi b/gyp/common_conditions.gypi
index 27dbf2a0e97960536f82076987aca5ca3fa5e53b..d8a93dbafdde9e041eab8dac716e428b62152909 100644
--- a/gyp/common_conditions.gypi
+++ b/gyp/common_conditions.gypi
@@ -216,10 +216,10 @@
           '-Wpointer-arith',
           '-Wsign-compare',
 
-          '-Wno-c++11-extensions',

[mtklein_C, 2015/02/04 14:14:46]

Not meaningful when using -std=c++11.

           '-Wno-unused-parameter',
         ],
         'cflags_cc': [
+          '-std=c++11',
           '-fno-rtti',
           '-Wnon-virtual-dtor',
           '-Wno-invalid-offsetof',  # GCC <4.6 is old-school strict about what is POD.
@@ -479,8 +479,6 @@
           }],
           [ 'skia_clang_build', {
             'cflags_cc': [
-                # Build in C++11 mode to make sure we'll have an easy time switching.
-                '-std=c++11',
                 '-Wno-unknown-warning-option',  # Allows unknown warnings.
                 '-Wno-deprecated',              # From Qt, via debugger (older Clang).
                 '-Wno-deprecated-register',     # From Qt, via debugger (newer Clang).