android: Update third_party/android_tools/

This is only used to get rid of an annoying issue where
third_party/android_tools/sdk/platform-tools/package.xml
appears as an untracked file, because it was not properly
listed in its .gitgnore file.

See https://chromium-review.googlesource.com/c/1449574

R=agrieve@chromium.org, jbudorick@chromium.org
BUG=NONE

Change-Id: I93e830a4e75e4ed28d597e7a79fd306f1bf192af
Reviewed-on: https://chromium-review.googlesource.com/c/1449667Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: David Turner <digit@chromium.org>
Cr-Commit-Position: refs/heads/master@{#628439}

DEPS

@@ -514,7 +514,7 @@ deps = {
   },
 
   'src/third_party/android_tools': {
-      'url': Var('chromium_git') + '/android_tools.git' + '@' + 'e958d6ea74442d4e0849bb8a018d215a0e78981d',
+      'url': Var('chromium_git') + '/android_tools.git' + '@' + '347a7c8078a009e98995985b7ab6ec6b35696dea',
       'condition': 'checkout_android_native_support',
   },