Update iron-autogrow-textarea to v2.1.0

This version contains (at least part) of a fix for bug 6500, in which
the commit message editor resized when it shouldn't. This is already
the version that the (next version of) gerrit-review will build with,
but want to make sure upstream is in sync.

Bug: Issue 6500
Change-Id: I40e83da3cfca557309afb7faa8fec8632f18b6e7

lib/js/bower_archives.bzl

@@ -45,13 +45,8 @@ def load_bower_archives():
   bower_archive(
     name = "iron-flex-layout",
     package = "iron-flex-layout",
-    version = "1.3.7",
-    sha1 = "4d4cf3232cf750a17a7df0a37476117f831ac633")
-  bower_archive(
-    name = "iron-form-element-behavior",
-    package = "iron-form-element-behavior",
-    version = "1.0.7",
-    sha1 = "7b5a79e02cc32f0918725dd26925d0df1e03ed12")
+    version = "2.0.0",
+    sha1 = "feae42cc5d2d948a50074f430cfb8ab28cb6dc9e")
   bower_archive(
     name = "iron-meta",
     package = "iron-meta",

lib/js/bower_components.bzl

@@ -45,7 +45,6 @@ def define_bower_components():
     deps = [
       ":iron-behaviors",
       ":iron-flex-layout",
-      ":iron-form-element-behavior",
       ":iron-validatable-behavior",
       ":polymer",
     ],
@@ -82,11 +81,6 @@ def define_bower_components():
     license = "//lib:LICENSE-polymer",
     deps = [ ":polymer" ],
   )
-  bower_component(
-    name = "iron-form-element-behavior",
-    license = "//lib:LICENSE-polymer",
-    deps = [ ":polymer" ],
-  )
   bower_component(
     name = "iron-input",
     license = "//lib:LICENSE-polymer",