Fix library dartdoc references

Change-Id: Idf83e7f5dfb95e0097fa73fa0a0ecd68c76d2ac9
Reviewed-on: https://dart-review.googlesource.com/35381
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Kevin Moore <kevmoo@google.com>

sdk/lib/convert/utf.dart

@@ -27,7 +27,7 @@ const int UNICODE_BOM_CHARACTER_RUNE = unicodeBomCharacterRune;
  *                                0x72, 0x67, 0x72, 0xc3, 0xb8, 0x64]);
  */
 const Utf8Codec utf8 = const Utf8Codec();
-/** Deprecated, use [tf8Codec] instead. */
+/** Deprecated, use [Utf8Codec] instead. */
 const Utf8Codec UTF8 = utf8;
 
 /**

sdk/lib/developer/timeline.dart

@@ -78,7 +78,7 @@ class Flow {
 ///
 /// [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 [endSync] can be used
+/// "Complete" events. [Timeline]'s [startSync] and [finishSync] can be used
 /// explicitly, or implicitly by wrapping a closure in [timeSync]. For exmaple:
 ///
 /// ```dart

sdk/lib/mirrors/mirrors.dart

@@ -820,7 +820,7 @@ abstract class ClassMirror implements TypeMirror, ObjectMirror {
    *
    * If this class is the result of a mixin application of the form S with M,
    * returns a class mirror on M. Otherwise returns a class mirror on
-   * [reflectee].
+   * the reflectee.
    */
   ClassMirror get mixin;