Roll android_small/icudtl_extra.dat into chromium

https://chromium.googlesource.com/chromium/deps/icu.git/+log/9a5af81f5..2b2ee71

2b2ee71 Add android_small/icudatl_extra.dat.
4ae379e Allow 'icupkg' to build data package without dependency check.
4de2cfd Merge the uptream pull/682 to prepare for Android extra data package.

Bug: chromium:969181
Change-Id: Ia4cca333a23cf1eda8c5ceb7da979a72ec7a1320
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1760863Reviewed-by: Jungshik Shin <jshin@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#688260}

DEPS

@@ -1010,7 +1010,7 @@ deps = {
     Var('chromium_git') + '/chromium/deps/hunspell_dictionaries.git' + '@' + 'ecb3c4f4ce2c13278699489bd6356a31e1ee4d11',
 
   'src/third_party/icu':
-    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + '9a5af81f58a2bc2ea7a887505e38b50021496194',
+    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + '2b2ee7158675555acb4d0d0cbb5dff71c00e7c54',
 
   'src/third_party/icu4j': {
       'packages': [