Changes around the launcher so that it only shows the most recently

ui/aura_shell/launcher/tabbed_launcher_button.cc

Index: ui/aura_shell/launcher/tabbed_launcher_button.cc
diff --git a/ui/aura_shell/launcher/tabbed_launcher_button.cc b/ui/aura_shell/launcher/tabbed_launcher_button.cc
index 620e57bffcf8d2702b803f7fe147204928efc80c..f1a1e277c870e47a01f1f352148b2abbe3e5d2fa 100644
--- a/ui/aura_shell/launcher/tabbed_launcher_button.cc
+++ b/ui/aura_shell/launcher/tabbed_launcher_button.cc
@@ -12,10 +12,8 @@
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/insets.h"
-#include "views/painter.h"
 
 namespace aura_shell {
-
 namespace internal {
 
 // The images drawn inside the background tab are drawn at this offset from
@@ -34,16 +32,22 @@ const int kBgBottomInset = 12;
 const int kBgRightInset = 8;
 
 // static
-SkBitmap* TabbedLauncherButton::bg_image_ = NULL;
+SkBitmap* TabbedLauncherButton::bg_image_1_ = NULL;
+SkBitmap* TabbedLauncherButton::bg_image_2_ = NULL;
+SkBitmap* TabbedLauncherButton::bg_image_3_ = NULL;
 
 TabbedLauncherButton::TabbedLauncherButton(views::ButtonListener* listener,
                                            LauncherButtonHost* host)
     : views::CustomButton(listener),
       host_(host) {
-  if (!bg_image_) {
+  if (!bg_image_1_) {
     ResourceBundle& rb = ResourceBundle::GetSharedInstance();
-    bg_image_ = new SkBitmap(
-        *rb.GetImageNamed(IDR_AURA_LAUNCHER_TABBED_BROWSER).ToSkBitmap());
+    bg_image_1_ = new SkBitmap(
+        *rb.GetImageNamed(IDR_AURA_LAUNCHER_TABBED_BROWSER_1).ToSkBitmap());
+    bg_image_2_ = new SkBitmap(
+        *rb.GetImageNamed(IDR_AURA_LAUNCHER_TABBED_BROWSER_2).ToSkBitmap());
+    bg_image_3_ = new SkBitmap(
+        *rb.GetImageNamed(IDR_AURA_LAUNCHER_TABBED_BROWSER_3).ToSkBitmap());
   }
 }
 
@@ -55,42 +59,28 @@ void TabbedLauncherButton::SetImages(const LauncherTabbedImages& images) {
 }
 
 gfx::Size TabbedLauncherButton::GetPreferredSize() {
-  if (images_.empty())
-    return gfx::Size(bg_image_->width(), bg_image_->height());
-
-  // Assume all images are the same size.
-  int num_images = static_cast<int>(images_.size());
-  int padding = (num_images - 1) * kImagePadding;
-  return gfx::Size(
-      std::max(kBgImageContentInset * 2 +
-               images_[0].image.width() * num_images + padding,
-               bg_image_->width()),
-      bg_image_->height());
+  return gfx::Size(bg_image_1_->width(), bg_image_1_->height());
 }
 
 void TabbedLauncherButton::OnPaint(gfx::Canvas* canvas) {
-  if (width() == bg_image_->width()) {
-    canvas->DrawBitmapInt(*bg_image_, 0, 0);
-  } else {
-    scoped_ptr<views::Painter> bg_painter(views::Painter::CreateImagePainter(
-        *bg_image_, gfx::Insets(kBgTopInset, kBgLeftInset, kBgBottomInset,
-                                kBgRightInset), true));
-    bg_painter->Paint(width(), height(), canvas);
-  }
+  SkBitmap* bg_image = NULL;
+  if (images_.size() <= 1)
+    bg_image = bg_image_1_;
+  else if (images_.size() == 2)
+    bg_image = bg_image_2_;
+  else
+    bg_image = bg_image_3_;
+  canvas->DrawBitmapInt(*bg_image, 0, 0);
 
   if (images_.empty())
     return;
 
-  int num_images = static_cast<int>(images_.size());
-  int padding = (num_images - 1) * kImagePadding;
-  int x = std::max(kBgImageContentInset,
-      (width() - num_images * images_[0].image.width() - padding) / 2);
+  // Only show the first icon.
+  // TODO(sky): if we settle on just 1 icon, then we should simplify surrounding
+  // code (don't use a vector of images).
+  int x = (width() - images_[0].image.width()) / 2;
   int y = (height() - images_[0].image.height()) / 2;
-  for (LauncherTabbedImages::const_iterator i = images_.begin();
-       i != images_.end(); ++i) {
-    canvas->DrawBitmapInt(i->image, x, y);
-    x += i->image.width() + kImagePadding;
-  }
+  canvas->DrawBitmapInt(images_[0].image, x, y);
 }
 
 bool TabbedLauncherButton::OnMousePressed(const views::MouseEvent& event) {