Fix no-op builds, caused by an incorrect output in //sandbox/mac:generate_stubs.

BUG=382931
TEST=Build sandbox twice. The second time it says "no work to do".

Review URL: https://codereview.chromium.org/332403005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278013 0039d316-1c4b-4281-b951-d872f2087c98

sandbox/mac/sandbox_mac.gypi

@@ -54,7 +54,7 @@
           ],
           'outputs': [
             '<(INTERMEDIATE_DIR)/<(generate_stubs_output_stem).cc',
-            '<(INTERMEDIATE_DIR)/<(generate_stubs_project)/<(generate_stubs_output_stem).h',
+            '<(SHARED_INTERMEDIATE_DIR)/<(generate_stubs_project)/<(generate_stubs_output_stem).h',
           ],
           'action': [
             'python',