clang/linux: Build with -g0 if fastbuild=1 is set (e.g. on the buildbots)

BUG=70000
TEST=clang/linux bots are 5x as fast.

Review URL: http://codereview.chromium.org/6324007

git-svn-id: http://src.chromium.org/svn/trunk/src/build@71765 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -549,6 +549,14 @@
               'debug_extra_cflags': '-g1',
             },
           }],
+          # Clang creates chubby debug information, which makes linking very
+          # slow. For now, don't create debug information with clang.  See
+          # http://crbug.com/70000
+          ['OS=="linux" and clang==1', {
+            'variables': {
+              'debug_extra_cflags': '-g0',
+            },
+          }],
         ],  # conditions for fastbuild.
       }],  # fastbuild!=0
       ['selinux==1', {