Switch the language standard to C++14.

This switches clang and GCC from -std=c++11 to -std=c++14.

No action is required for MSVC++, where /std:c++14 is already the
default.

This is like Chromium 5a9b923e3713
(https://chromium-review.googlesource.com/583635), for mini_chromium.

Change-Id: I0fe3fd08efbdb50fa0783d4aaa7453b72cff4d78
Reviewed-on: https://chromium-review.googlesource.com/714576
Reviewed-by: Leonard Mosescu <mosescu@chromium.org>
diff --git a/build/common.gypi b/build/common.gypi
index aac7669..dd9612b 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -66,7 +66,7 @@
 
           'conditions': [
             ['clang!=0', {
-              'CLANG_CXX_LANGUAGE_STANDARD': 'c++11',  # -std=c++11
+              'CLANG_CXX_LANGUAGE_STANDARD': 'c++14',  # -std=c++14
 
               # Don't link in libarclite_macosx.a, see http://crbug.com/156530.
               'CLANG_LINK_OBJC_RUNTIME': 'NO',  # No -fobjc-link-runtime
@@ -138,7 +138,7 @@
         'cflags_cc': [
           '-fno-rtti',
           '-fvisibility-inlines-hidden',
-          '-std=c++11',
+          '-std=c++14',
         ],
         'defines': [
           '_FILE_OFFSET_BITS=64',