[Analyzer] Remove period from LSP commit characters

Change-Id: I7eef065f2db39f6b95fcdffbeda40bd4b08aca3b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/169081
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Danny Tuppeny <danny@tuppeny.com>
diff --git a/pkg/analysis_server/lib/src/lsp/constants.dart b/pkg/analysis_server/lib/src/lsp/constants.dart
index 460fa5e..275030d 100644
--- a/pkg/analysis_server/lib/src/lsp/constants.dart
+++ b/pkg/analysis_server/lib/src/lsp/constants.dart
@@ -16,7 +16,11 @@
 ///
 ///     myLongFunctionName();
 ///     print(myLong^)
-const dartCompletionCommitCharacters = ['.', '('];
+///
+/// The `.` is not included because it falsely triggers whenver typing a
+/// cascade (`..`), inserting the very first completion instead of just a second
+/// period.
+const dartCompletionCommitCharacters = ['('];
 
 /// Set the characters that will cause the editor to automatically
 /// trigger completion.