Remove webContents check when download starts

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java

Index: chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java b/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java
index 44a09a0e0bea3c73723d6b21805923ab47e6cf49..37a2777081016085f4d5f9051f90c9e2b074be73 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java
@@ -13,9 +13,13 @@ import android.view.View;
 import android.widget.TextView;
 
 import org.chromium.base.ApplicationStatus;
+import org.chromium.base.ContextUtils;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
+import org.chromium.chrome.browser.tab.Tab;
+import org.chromium.chrome.browser.tabmodel.TabModelSelector;
+import org.chromium.content_public.browser.WebContents;
 import org.chromium.ui.base.WindowAndroid;
 import org.chromium.ui.base.WindowAndroid.PermissionCallback;
 
@@ -186,6 +190,38 @@ public class DownloadController {
         builder.create().show();
     }
 
+    /**
+     * Called when a download is started.
+     */
+    @CalledByNative
+    private void onDownloadStarted() {
+        DownloadUtils.showDownloadStartToast(ContextUtils.getApplicationContext());
+    }
+
+    /**
+     * Close a tab if it is blank.'

[David Trainor- moved to gerrit, 2017/05/09 05:57:09]

Remove ' at the end?

[qinmin, 2017/05/10 16:09:03]

Done.

+     * @param Tab Tab to close
+     * @return true iff the tab was (already) closed.
+     */
+    @CalledByNative
+    static boolean closeTabIfBlank(Tab tab) {
+        if (tab == null) return true;
+        WebContents contents = tab.getWebContents();
+        boolean isInitialNavigation = contents == null
+                || contents.getNavigationController().isInitialNavigation();
+        if (isInitialNavigation) {
+            // Tab is created just for download, close it.
+            Activity activity = tab.getWindowAndroid().getActivity().get();

[David Trainor- moved to gerrit, 2017/05/09 05:57:09]

tab.getTabModelSelector()?  Can we ever host this outside a ChromeActivity?

[qinmin, 2017/05/10 16:09:03]

Done.

+            if (!(activity instanceof ChromeActivity)) return true;
+
+            TabModelSelector selector = ((ChromeActivity) activity).getTabModelSelector();
+            if (selector == null) return true;
+            if (selector.getModel(tab.isIncognito()).getCount() == 1) return false;
+            return selector.closeTab(tab);

[David Trainor- moved to gerrit, 2017/05/09 05:57:09]

If this is correct, can we update the javadoc?  Does this function return true
if it closed the tab, or if it was already closed?  This looks like it'll return
true when we actually close the tab, but the javadoc makes me think the
opposite.

[qinmin, 2017/05/10 16:09:03]

selector.closeTab() returns true if the tab is found, or false otherwise. Since
the tab is non-null here, not found means we are passing a wrong
TabModelSelector. So this is correct.
However, since the TabModelSelector is retrieved from the tab, so closeTab()
should not return false here. So changed this into an assert.

+        }
+        return false;
+    }
+
     // native methods
     private native void nativeInit();
     private native void nativeOnAcquirePermissionResult(