Elements. Migrate ElementsTypesMixin, part#4

Change-Id: I66c188d2c8502c753fdc1c64d1f2759022b86bc9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/409820
Reviewed-by: Phil Quitslund <pquitslund@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

https://dart.googlesource.com/sdk/+/9d96cd9d9c24c494c44bf74c2c2091ad022b71cf

DEPS

diff --git a/DEPS b/DEPS
index df1b581..7630483 100644
--- a/DEPS
+++ b/DEPS
@@ -237,7 +237,7 @@
 ]
 
 deps = {
-  'flutter/engine/src/flutter/third_party/dart': Var('dart_git') + '/sdk' + '@' + '49ee8515ab4c4183df16c6ac192447a49c07fe38',
+  'flutter/engine/src/flutter/third_party/dart': Var('dart_git') + '/sdk' + '@' + '9d96cd9d9c24c494c44bf74c2c2091ad022b71cf',
 
   'flutter': Var('flutter_git') + '/mirrors/flutter' + '@' + 'c2229a884b600a8f769648bf56ec0dab8c5c676e',
 

commits.json

diff --git a/commits.json b/commits.json
index d68c4b7..f1ed864 100644
--- a/commits.json
+++ b/commits.json
@@ -1,4 +1,4 @@
 {
   "flutter":"c2229a884b600a8f769648bf56ec0dab8c5c676e",
-  "flutter/engine/src/flutter/third_party/dart":"49ee8515ab4c4183df16c6ac192447a49c07fe38"
+  "flutter/engine/src/flutter/third_party/dart":"9d96cd9d9c24c494c44bf74c2c2091ad022b71cf"
 }
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