Elements. Migrate NullSafeApiVerifier.

Change-Id: I012630edfef67c69cd8d6c77fbb79f20ba7ba521
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/395041
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

https://dart.googlesource.com/sdk/+/76e3198792090daa1230974b1439878bf316df69

DEPS

diff --git a/DEPS b/DEPS
index 252cc8a..133d47d 100644
--- a/DEPS
+++ b/DEPS
@@ -260,7 +260,7 @@
 
   'engine/src/flutter': Var('flutter_git') + '/mirrors/engine' + '@' + 'e97b148e796d4d68c6c0a98a78427e4d8ccbafa6',
 
-  'engine/src/flutter/third_party/dart': Var('dart_git') + '/sdk' + '@' + '68886242d8c88733d03e83c893785abd8dbd0223',
+  'engine/src/flutter/third_party/dart': Var('dart_git') + '/sdk' + '@' + '76e3198792090daa1230974b1439878bf316df69',
 
   'flutter': Var('flutter_git') + '/mirrors/flutter' + '@' + 'd7e1f03ee0c2aaebbc99b415efefdb19d4e1c261',
 

commits.json

diff --git a/commits.json b/commits.json
index 37adf8d..e016145 100644
--- a/commits.json
+++ b/commits.json
@@ -1,5 +1,5 @@
 {
   "engine/src/flutter":"e97b148e796d4d68c6c0a98a78427e4d8ccbafa6",
-  "engine/src/flutter/third_party/dart":"68886242d8c88733d03e83c893785abd8dbd0223",
+  "engine/src/flutter/third_party/dart":"76e3198792090daa1230974b1439878bf316df69",
   "flutter":"d7e1f03ee0c2aaebbc99b415efefdb19d4e1c261"
 }
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