Removes Vietnamese VNI input method.

TBR=suzhe@chromium.org
BUG=487914
TEST=Verified on linux_chromeos.

Review URL: https://codereview.chromium.org/1144493005

Cr-Commit-Position: refs/heads/master@{#329791}

chrome/browser/resources/chromeos/input_method/google_input_tools_manifest.json

@@ -667,19 +667,6 @@
       ],
       "input_view": "inputview.html#id=m17n:vi_viqr&language=vi&passwordLayout=us-ltr&name=keyboard_vietnamese_viqr"
     },
-    {
-      "name": "__MSG_keyboard_vietnamese_vni__",
-      "type": "ime",
-      "id": "vkd_vi_vni",
-      "description": "",
-      "language": [
-        "vi"
-      ],
-      "layouts": [
-        "us"
-      ],
-      "input_view": "inputview.html#id=m17n:vi_vni&language=vi&passwordLayout=us-ltr&name=keyboard_vietnamese_vni"
-    },
     {
       "name": "__MSG_keyboard_arabic__",
       "type": "ime",