WebUsb Android chooser UI

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

Index: chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java b/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
index 89c697f81a768824426ea363e0cfd0b9fdfdf8f6..69fbbcae936982685a6e1f839a515bd2c5f81119 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
@@ -368,6 +368,28 @@ public class ItemChooserDialog {
     }

[Finnur, 2016/03/14 11:36:50]

Hmm... I just discovered that the only (previous) consumer of this class
(Bluetooth) no longer uses this function in the manner it was intended (add a
whole list). This function should therefore be removed because Bluetooth now
adds items one by one, just like the UsbChooser does and having two ways of
doing the same thing is confusing. 

That means this function should be converted to use your new addItemToList:

https://code.google.com/p/chromium/codesearch#chromium/src/chrome/android/jav...

And that also makes me wonder if status PROGRESS_UPDATE_AVAILABLE is ever used.
If not, it should also be removed.

[juncai, 2016/03/16 00:40:35]

Done.

 
     /**
+    * Add an item to the end of the list to show in the dialog.
+    *
+    * @param item The item to be added to the end of the chooser.
+    */
+    public void addItemToList(ItemChooserRow item) {
+        mProgressBar.setVisibility(View.GONE);
+        mItemAdapter.add(item);
+        setState(State.DISCOVERY_IDLE);
+    }
+
+    /**
+    * Remove an item that is shown in the dialog.
+    *
+    * @param item The item to be removed in the chooser.
+    */
+    public void removeItemFromList(ItemChooserRow item) {
+        mProgressBar.setVisibility(View.GONE);

[Finnur, 2016/03/14 11:36:50]

Why is this necessary? 

[juncai, 2016/03/16 00:40:35]

Removed.

Done.

+        mItemAdapter.remove(item);
+        setState(State.DISCOVERY_IDLE);

[Finnur, 2016/03/14 11:36:50]

What does the dialog look like if you add one item and subsequently remove it?
Does it show "no items", or something?

[juncai, 2016/03/16 00:40:35]

It shows "No devices found.".

+    }

[Finnur, 2016/03/14 11:36:49]

These new API functions need to be tested in ItemChooserDialogTest.java.

[juncai, 2016/03/16 00:40:35]

Done.

+
+    /**
      * Indicates the chooser that no more items will be added.
      */
     public void setIdleState() {