update pub to get latest dartdevc fixes

CHANGELOG.md

Index: CHANGELOG.md
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0d30e09bfba03b1aa6f75b805d01d901880662a6..f512435e3716fe83a54db20049eb01ec4a6d1238 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,15 @@
 
   * `pub get` and `pub upgrade` properly produce an error message and exit code
     when no network is present.
+  * Bug fixes for dartdevc support in `pub serve`.
+    * Fixed module config invalidation logic so modules are properly
+      recalculated when package layout changes.
+    * Fixed exception when handling require.js errors that aren't script load
+      errors.
+    * Fixed an issue where requesting the bootstrap.js file before the dart.js
+      file would result in a 404.
+    * Fixed a Safari issue during bootstrapping (note that Safari is still not
+      officially supported but does work for trivial examples).
 
 ## 1.24.0
 
@@ -161,7 +170,7 @@
 * Pub
 
   * `pub build` and `pub serve`
-  
+
     * Added support for the Dart Development Compiler.
 
       Unlike dart2js, this new compiler is modular, which allows pub to do
@@ -207,7 +216,7 @@
       transformer.
 
   * `pub publish`
-  
+
     * Added support for the UNLICENSE file.
 
     * Packages that depend on the Flutter SDK may be published.