Add GTX lib for accessibility testing.

Bug: 856622
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I250a7899963fa1d43aabb6419e7044677b61b975
Reviewed-on: https://chromium-review.googlesource.com/1114918
Commit-Queue: Lindsay Pasricha <[email protected]>
Reviewed-by: Rohit Rao <[email protected]>
Reviewed-by: Justin Cohen <[email protected]>
Cr-Commit-Position: refs/heads/master@{#585022}
diff --git a/DEPS b/DEPS
index deacce1f..99d6194 100644
--- a/DEPS
+++ b/DEPS
@@ -275,6 +275,11 @@
       'condition': 'checkout_ios',
   },
 
+  'src/ios/third_party/gtx/src': {
+      'url': Var('chromium_git') + '/external/github.com/google/GTXiLib.git' + '@' + '2d2bf1408cfee8559cd672129959bba54a5cfa2b',
+      'condition': 'checkout_ios',
+  },
+
   'src/ios/third_party/firebase': {
       'packages': [
         {