Address some TODOs for ChooserBubbleDelegate class

chrome/browser/ui/cocoa/website_settings/chooser_bubble_ui_cocoa.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/website_settings/chooser_bubble_ui_cocoa.h"
 
 #include <algorithm>
 #include <cmath>
 #include <vector>
 
@@ skipping 276 matching lines @@
   } else {
     [[self window] setFrame:bubbleFrame display:NO];
     [self setAnchorPoint:[self getExpectedAnchorPoint]];
     [self showWindow:nil];
     [[self window] makeFirstResponder:nil];
     [[self window] setInitialFirstResponder:connectButton_.get()];
   }
 }
 
 - (NSInteger)numberOfRowsInTableView:(NSTableView*)tableView {
-  const std::vector<base::string16>& device_names =
-      chooserBubbleDelegate_->GetOptions();
-  if (device_names.empty()) {
-    return 1;
-  } else {
-    return static_cast<NSInteger>(device_names.size());
-  }
+  size_t num_options = chooserBubbleDelegate_->NumOptions();
+  return num_options == 0 ? 1 : static_cast<NSInteger>(num_options);

[Peter Kasting, 2016/01/04 21:02:52]

Nit: Shorter:

  return static_cast<NSInteger>(std::min(chooserBubbleDelegate_->NumOptions(),
1));

[juncai, 2016/01/04 22:44:46]

I think here it needs to use std::max instead of std::min.

[Peter Kasting, 2016/01/04 23:54:00]

Oops!  Yes.

 }
 
 - (id)tableView:(NSTableView*)tableView
     objectValueForTableColumn:(NSTableColumn*)tableColumn
                           row:(NSInteger)rowIndex {
-  const std::vector<base::string16>& device_names =
-      chooserBubbleDelegate_->GetOptions();
-  if (device_names.empty()) {
+  NSInteger num_options =
+      static_cast<NSInteger>(chooserBubbleDelegate_->NumOptions());
+  if (num_options == 0) {
     DCHECK(rowIndex == 0);

[Peter Kasting, 2016/01/04 21:02:52]

Nit: While here: DCHECK_EQ(0, rowIndex);

[juncai, 2016/01/04 22:44:46]

Done.

     return l10n_util::GetNSString(IDS_CHOOSER_BUBBLE_NO_DEVICES_FOUND_PROMPT);
   } else {

[Peter Kasting, 2016/01/04 21:02:52]

Nit: While here: No "else" after return (multiple places)

[juncai, 2016/01/04 22:44:46]

Done.

-    if (rowIndex >= 0 &&
-        rowIndex < static_cast<NSInteger>(device_names.size())) {
-      return base::SysUTF16ToNSString(device_names[rowIndex]);
+    if (rowIndex >= 0 && rowIndex < num_options) {

[Peter Kasting, 2016/01/04 21:02:52]

Should this be DCHECKs instead of conditionals?  How can we be called with an
out-of-bounds value?

[juncai, 2016/01/04 22:44:46]

Done.

+      return base::SysUTF16ToNSString(
+          chooserBubbleDelegate_->GetOption(static_cast<size_t>(rowIndex)));
     } else {
       return @"";
     }
   }
 }
 
 - (BOOL)tableView:(NSTableView*)aTableView
     shouldEditTableColumn:(NSTableColumn*)aTableColumn
                       row:(NSInteger)rowIndex {
   return NO;
@@ skipping 11 matching lines @@
   // |tableView_| will automatically selects the next item if the current
   // item is removed, so here it tracks if the removed item is the item
   // that was previously selected, if so, deselect it.
   if ([tableView_ selectedRow] == index)
     [tableView_ deselectRow:index];
 
   [self updateTableView];
 }
 
 - (void)updateTableView {
-  const std::vector<base::string16>& device_names =
-      chooserBubbleDelegate_->GetOptions();
-  [tableView_ setEnabled:!device_names.empty()];
+  [tableView_ setEnabled:chooserBubbleDelegate_->NumOptions() > 0];
   [tableView_ reloadData];
 }
 
 - (void)tableViewSelectionDidChange:(NSNotification*)aNotification {
   [connectButton_ setEnabled:[tableView_ numberOfSelectedRows] > 0];
 }
 
 - (void)updateAnchorPosition {
   [self setParentWindow:[self getExpectedParentWindow]];
   [self setAnchorPoint:[self getExpectedAnchorPoint]];
@@ skipping 134 matching lines @@
 }
 
 void ChooserBubbleUiCocoa::UpdateAnchorPosition() {
   [chooser_bubble_ui_controller_ updateAnchorPosition];
 }
 
 void ChooserBubbleUiCocoa::OnOptionsInitialized() {
   [chooser_bubble_ui_controller_ onOptionsInitialized];
 }
 
-void ChooserBubbleUiCocoa::OnOptionAdded(int index) {
-  [chooser_bubble_ui_controller_ onOptionAdded:index];
+void ChooserBubbleUiCocoa::OnOptionAdded(size_t index) {
+  [chooser_bubble_ui_controller_ onOptionAdded:static_cast<NSInteger>(index)];
 }
 
-void ChooserBubbleUiCocoa::OnOptionRemoved(int index) {
-  [chooser_bubble_ui_controller_ onOptionRemoved:index];
+void ChooserBubbleUiCocoa::OnOptionRemoved(size_t index) {
+  [chooser_bubble_ui_controller_ onOptionRemoved:static_cast<NSInteger>(index)];
 }
 
 void ChooserBubbleUiCocoa::OnBubbleClosing() {
   chooser_bubble_ui_controller_ = nil;
 }