[Home] Fix status bar color on tab mode switch

The status bar's color would incorrectly switch when changing tab
models in the tab switcher due to tab's onShow being called. The
tab switcher logic was not handled correctly since the Chrome Home
test existed in ChromeActivity instead of ChromeTabbedActivity;
this change moves that logic.

This change also adds a special case for the incognito NTP, since
that page is completely dark, that status bar should be too.

BUG=708680

Review-Url: https://codereview.chromium.org/2803673003
Cr-Commit-Position: refs/heads/master@{#462878}

chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java

@@ -612,6 +612,11 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
                         (ControlContainer) findViewById(R.id.control_container);
                 controlContainer.getToolbarResourceAdapter().invalidate(null);
             }
+
+            @Override
+            public void onContentChanged(Tab tab) {
+                if (getBottomSheet() != null) setStatusBarColor(tab, tab.getDefaultThemeColor());
+            }
         };
 
         if (mAssistStatusHandler != null) {
@@ -794,11 +799,6 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
     protected void setStatusBarColor(Tab tab, int color) {
         int statusBarColor = (tab != null && tab.isDefaultThemeColor())
                 ? Color.BLACK : ColorUtils.getDarkenedColorForStatusBar(color);
-        if (getBottomSheet() != null) {
-            statusBarColor =
-                    ApiCompatibilityUtils.getColor(getResources(), R.color.default_primary_color);
-            getBottomSheet().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR);
-        }
         ApiCompatibilityUtils.setStatusBarColor(getWindow(), statusBarColor);
     }
 

chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java

@@ -1838,6 +1838,22 @@ public class ChromeTabbedActivity extends ChromeActivity implements OverviewMode
     @Override
     protected void setStatusBarColor(Tab tab, int color) {
         if (DeviceFormFactor.isTablet(getApplicationContext())) return;
+
+        // If Chrome Home is enabled, the super of this function is not called because it only
+        // performs unnecessary transformations on the theme color.
+        if (getBottomSheet() != null) {
+            color = ApiCompatibilityUtils.getColor(getResources(), R.color.default_primary_color);
+            getBottomSheet().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR);
+
+            // Special case the incognito NTP and the tab switcher.
+            if ((tab != null && NewTabPage.isNTPUrl(tab.getUrl()) && tab.isIncognito())
+                    || isInOverviewMode()) {
+                color = Color.BLACK;
+            }
+            ApiCompatibilityUtils.setStatusBarColor(getWindow(), color);
+            return;
+        }
+
         super.setStatusBarColor(tab, isInOverviewMode() ? Color.BLACK : color);
     }