Adds ability to render omnibox as a view above the page.

chrome/browser/ui/views/frame/contents_container.cc

Index: chrome/browser/ui/views/frame/contents_container.cc
diff --git a/chrome/browser/ui/views/frame/contents_container.cc b/chrome/browser/ui/views/frame/contents_container.cc
index 7b6981fd7dc542eee988d0824e23d7693e66c229..31feb37fade5d5c920fd6bb80f24013b184f155d 100644
--- a/chrome/browser/ui/views/frame/contents_container.cc
+++ b/chrome/browser/ui/views/frame/contents_container.cc
@@ -5,24 +5,55 @@
 #include "chrome/browser/ui/views/frame/contents_container.h"
 
 #include "base/logging.h"
+#include "ui/views/layout/fill_layout.h"
 
 using content::WebContents;
 
+class ContentsContainer::HeaderView : public views::View {
+ public:
+  HeaderView();
+
+  bool should_show() { return child_count() && child_at(0)->visible(); }
+
+ protected:
+  // views::View overrides:
+  virtual void ChildPreferredSizeChanged(views::View* child) OVERRIDE;
+
+ private:
+  bool child_visibile_;
+
+  DISALLOW_COPY_AND_ASSIGN(HeaderView);
+};
+
+ContentsContainer::HeaderView::HeaderView() : child_visibile_(false) {}
+
+void ContentsContainer::HeaderView::ChildPreferredSizeChanged(
+    views::View* child) {
+  if (parent() && (child->visible() || child_visibile_))
+    parent()->Layout();
+  child_visibile_ = child->visible();
+}
+
 // static
 const char ContentsContainer::kViewClassName[] =
     "browser/ui/views/frame/ContentsContainer";
 
 ContentsContainer::ContentsContainer(views::View* active)
-    : active_(active),
+    : header_(new HeaderView()),
+      active_(active),
       preview_(NULL),
       preview_web_contents_(NULL),
       active_top_margin_(0) {
   AddChildView(active_);
+  header_->SetLayoutManager(new views::FillLayout);
+  AddChildView(header_);
 }
 
 ContentsContainer::~ContentsContainer() {
 }
 
+views::View* ContentsContainer::header() { return header_; }
+
 void ContentsContainer::MakePreviewContentsActiveContents() {
   DCHECK(preview_);
 
@@ -64,9 +95,18 @@ gfx::Rect ContentsContainer::GetPreviewBounds() {
 }
 
 void ContentsContainer::Layout() {
-  // The active view always gets the full bounds.
-  active_->SetBounds(0, active_top_margin_, width(),
-                     std::max(0, height() - active_top_margin_));
+  int content_y = active_top_margin_;
+  int content_height = std::max(0, height() - content_y);
+  if (header_->should_show()) {
+    gfx::Size header_pref = header_->GetPreferredSize();
+    int header_height = std::min(content_height, header_pref.height());
+    content_height -= header_height;
+    header_->SetBounds(0, content_y, width(), header_height);
+    content_y += header_height;
+  } else {
+    header_->SetBoundsRect(gfx::Rect());
+  }
+  active_->SetBounds(0, content_y, width(), content_height);
 
   if (preview_)
     preview_->SetBounds(0, 0, width(), height());