Fix location bar search icon having the wrong tint on tablet

Intialize the colors properly in StatusMediator so that the icon tint
is set correctly when tint update is never called.

Bug: 953975
Change-Id: I21909656d412667dd8958738884c60879d4e1295
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1575121Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: Becky Zhou <huayinz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#652581}

chrome/android/java/src/org/chromium/chrome/browser/omnibox/status/StatusMediator.java

@@ -45,6 +45,7 @@ class StatusMediator {
 
     StatusMediator(PropertyModel model) {
         mModel = model;
+        updateColorTheme();
     }
 
     /**