Fix some typos.

Change-Id: I86997801dd4ae210d79340d76006b4865fdee814
Reviewed-on: https://dart-review.googlesource.com/65022
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Devon Carew <devoncarew@google.com>
diff --git a/pkg/analyzer/lib/src/task/strong/checker.dart b/pkg/analyzer/lib/src/task/strong/checker.dart
index 6cfa78a..a1ee440 100644
--- a/pkg/analyzer/lib/src/task/strong/checker.dart
+++ b/pkg/analyzer/lib/src/task/strong/checker.dart
@@ -1425,7 +1425,7 @@
   /// [covariantInterfaces] that may allow those members to be called in an
   /// unsound way.
   ///
-  /// See [_findCovariantChecksForMember] for more information and an exmaple.
+  /// See [_findCovariantChecksForMember] for more information and an example.
   Set<Element> _findCovariantChecks(Iterable<ExecutableElement> members,
       Iterable<ClassElement> covariantInterfaces,
       [Set<Element> covariantChecks]) {
diff --git a/sdk/lib/developer/timeline.dart b/sdk/lib/developer/timeline.dart
index f1ceda4..e838a1f 100644
--- a/sdk/lib/developer/timeline.dart
+++ b/sdk/lib/developer/timeline.dart
@@ -79,7 +79,7 @@
 /// [Timeline]'s methods add synchronous events to the timeline. When
 /// generating a timeline in Chrome's tracing format, using [Timeline] generates
 /// "Complete" events. [Timeline]'s [startSync] and [finishSync] can be used
-/// explicitly, or implicitly by wrapping a closure in [timeSync]. For exmaple:
+/// explicitly, or implicitly by wrapping a closure in [timeSync]. For example:
 ///
 /// ```dart
 /// Timeline.startSync("Doing Something");