alternate ntp (cros/partial-win): add tab-related stuff and toolbar/tab background change

chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc

Index: chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc
diff --git a/chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc b/chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc
index 3fd204f9917c84592fb7aa8e0569d9aaf838a51b..cf45b4c60b32d76e83422b2fe07877694485a8ff 100644
--- a/chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc
+++ b/chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc
@@ -12,6 +12,9 @@
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/search/search.h"
+#include "chrome/browser/ui/search/search_delegate.h"
+#include "chrome/browser/ui/search/search_model.h"
 #include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "chrome/browser/ui/tabs/tab_menu_model.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ -166,6 +169,8 @@ BrowserTabStripController::BrowserTabStripController(Browser* browser,
       browser_(browser),
       hover_tab_selector_(model) {
   model_->AddObserver(this);
+  browser_->search_model()->AddObserver(this);
+  browser_->search_delegate()->toolbar_search_animator().AddObserver(this);
 
   local_pref_registrar_.Init(g_browser_process->local_state());
   local_pref_registrar_.Add(prefs::kTabStripLayoutType, this);
@@ -179,6 +184,8 @@ BrowserTabStripController::~BrowserTabStripController() {
     context_menu_contents_->Cancel();
 
   model_->RemoveObserver(this);
+  browser_->search_delegate()->toolbar_search_animator().RemoveObserver(this);
+  browser_->search_model()->RemoveObserver(this);
 }
 
 void BrowserTabStripController::InitFromModel(TabStrip* tabstrip) {
@@ -433,6 +440,48 @@ void BrowserTabStripController::TabBlockedStateChanged(
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+// BrowserTabStripController, chrome::search::SearchModelObserver:
+
+void BrowserTabStripController::ModeChanged(const chrome::search::Mode& mode) {
+  // Mode has changed, set tab data based on new mode, which will trigger
+  // repainting of tab's background.
+  int active_index = GetActiveIndex();
+  DCHECK(active_index != -1);

[sky, 2012/06/27 04:18:36]

Why both the DCHECK and the return? And why no DCHECK on 479? Shouldn't this
only be sent when the active index is valid? I think you should ensure that
happens by updating the toolbarsearchanimator before the tabstrip.

[kuan, 2012/06/27 10:29:52]

when reviewing the cl for 1993 repo, u asked me to make sure active index is not
-1, so i added DCHECK and returned if so.
this callback is not for ToolbarSearchAnimator, it's for SearchModelObserver.

@479, i didn't DCHECK if |tab_contents| doesn't exist in tab model, 'cos then
there's no TabRendererData to update.  this update is solely for the purpose of
painting the tab at 100% opacity if it's reactivated.  if the tab doesn't exist,
then there's no way to reactivate it. 

i apologize but i'm kinda confused what to modify here.

[kuan, 2012/06/27 13:11:33]

actually, it was when reviewing THIS cl that u asked me to make sure that active
index != 1, not the cl for 1993 repo.

[sky, 2012/06/27 14:11:44]

Ya, sorry. The confusion is on my part too. The question is, does the searchmode
only change when we have active tabs? If so, DCHECK, if it can change when there
are no active tabs than conditional return. Ask Dave for which it is.

[dhollowa, 2012/06/27 15:05:20]

Yes, when there are no tabs then no SearchModel changes can happen.  Model
changes only happen when the active tab changes, or there are changes to the
active tab.

[kuan, 2012/06/27 16:38:14]

so i kept code as is: both DCHECK and conditional return.

[dhollowa, 2012/06/27 17:54:59]

You can remove the conditional return.  |ModeChanged| only fires with non-null
tab, aka active_index != -1.

+  if (active_index == -1)
+    return;
+  SetTabDataAt(browser_->GetTabContentsAt(active_index), active_index);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// BrowserTabStripController, chrome::search::ToolbarSearchAnimator::Observer:
+
+void BrowserTabStripController::OnToolbarBackgroundAnimatorProgressed() {
+  // We're fading in the tab background, set tab data based on new background
+  // state and possibly opacity value, which will trigger repainting of tab's
+  // background.
+  int active_index = GetActiveIndex();
+  DCHECK(active_index != -1);
+  if (active_index == -1)
+    return;
+  SetTabDataAt(browser_->GetTabContentsAt(active_index), active_index);
+}
+
+void BrowserTabStripController::OnToolbarBackgroundAnimatorCanceled(
+    TabContents* tab_contents) {
+  // Fade in of tab background has been canceled.
+  // If |tab_contents| is not NULL and tab strip model contains |tab_contents|,
+  // set tab data so that |TabRendererData::background_state| and
+  // |TabRendererData::new_background_opacity| will be reset; repainting
+  // of tab's background will be triggered in the process.
+  if (!tab_contents)
+    return;
+  int index = model_->GetIndexOfTabContents(tab_contents);
+  if (index == -1)
+    return;
+  SetTabDataAt(tab_contents, index);
+}
+
+////////////////////////////////////////////////////////////////////////////////
 // BrowserTabStripController, content::NotificationObserver implementation:
 
 void BrowserTabStripController::Observe(int type,
@@ -474,6 +523,19 @@ void BrowserTabStripController::SetTabRendererDataFromModel(
   data->mini = model_->IsMiniTab(model_index);
   data->blocked = model_->IsTabBlocked(model_index);
   data->app = tab_contents->extension_tab_helper()->is_app();
+  data->mode = browser_->search_model()->mode().mode;
+  if (data->mode == chrome::search::Mode::MODE_SEARCH) {
+    // Get current state of background animation to paint for SEARCH mode.
+    browser_->search_delegate()->toolbar_search_animator().
+        GetCurrentBackgroundState(&data->background_state,
+                                  &data->new_background_opacity);
+  } else {
+    data->background_state =
+        chrome::search::ToolbarSearchAnimator::BACKGROUND_STATE_DEFAULT;
+    // Valid opacity value of double data type is 0f to 1f, so use -1f to
+    // indicate an invalid value.
+    data->new_background_opacity = -1.0f;
+  }
 }
 
 void BrowserTabStripController::SetTabDataAt(