[dartdevc] Synchronizing dart_library.js with internal hot restart change.

See: cl/352082170
Change-Id: I6bb9cc27997d1ce2117c58d5e3b3ee3a299e7c2d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/180260
Commit-Queue: Nicholas Shahan <nshahan@google.com>
Reviewed-by: Nicholas Shahan <nshahan@google.com>
diff --git a/pkg/dev_compiler/lib/js/legacy/dart_library.js b/pkg/dev_compiler/lib/js/legacy/dart_library.js
index 3c8be22..9be3935 100644
--- a/pkg/dev_compiler/lib/js/legacy/dart_library.js
+++ b/pkg/dev_compiler/lib/js/legacy/dart_library.js
@@ -224,7 +224,7 @@
   function reload(clearState) {
     // TODO(jmesserly): once we've rolled out `clearState` make it the default,
     // and eventually remove the parameter.
-    if (clearState == null) clearState = false;
+    if (clearState == null) clearState = true;
 
 
     // TODO(jmesserly): we may want to change these APIs to use the