Enable the First Configuration of BrowserFocusTest.TabsRememberFocus

The first kFocusPage config has been skipped since at least the initial
public commit and appears to be an oversight.

https://chromium.googlesource.com/chromium/src/+blame/09911bf300f1a419907a9412154760efd0b7abc3/chrome/browser/browser_focus_uitest.cc#186

BUG=

Change-Id: If17bfc7594d57ea62e5508b8912abcd628d5a0bf
Reviewed-on: https://chromium-review.googlesource.com/964608Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Robert Liao <robliao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543443}

chrome/browser/ui/browser_focus_uitest.cc

@@ -279,7 +279,7 @@ IN_PROC_BROWSER_TEST_F(BrowserFocusTest, TabsRememberFocus) {
     { false, true, false, true, false }
   };
 
-  for (int i = 1; i < 3; i++) {
+  for (int i = 0; i < 3; i++) {
     for (int j = 0; j < 5; j++) {
       // Activate the tab.
       browser()->tab_strip_model()->ActivateTabAt(j, true);