WebKit build needs to be told where to look for ICU package....

src/extensions/experimental/experimental.gyp

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 {
   'variables': {
-    'icu_src_dir%': '',
+    # TODO(cira): Find out how to pass this value for arbitrary embedder.
+    # Chromium sets it in common.gypi and does force include of that file for
+    # all sub projects.
+    'icu_src_dir%': '../../../../third_party/icu',

[Mads Ager (chromium), 2011/01/24 06:53:35]

This really should be handled in some other way than hard-coding a relative path
here. I'll land this for now since it is in an experimental directory.

   },
   'targets': [
     {
       'target_name': 'i18n_api',
       'type': 'static_library',
       'sources': [
         'i18n-extension.cc',
         'i18n-extension.h',
       ],
       'include_dirs': [
         '<(icu_src_dir)/public/common',
         '../..',
       ],
       'dependencies': [
         '<(icu_src_dir)/icu.gyp:*',
         '../../../tools/gyp/v8.gyp:v8',
       ],
     },
   ],  # targets
 }