Hook up SetInstantPreviewHeight for ChromeOS.

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

Index: chrome/browser/ui/views/frame/contents_container.h
diff --git a/chrome/browser/ui/views/frame/contents_container.h b/chrome/browser/ui/views/frame/contents_container.h
index 3227688ad56d91f6b0f1df7737597a026d066252..2febbc667c5b11fe3a3793d7722f8e0b7f12bcb1 100644
--- a/chrome/browser/ui/views/frame/contents_container.h
+++ b/chrome/browser/ui/views/frame/contents_container.h
@@ -45,6 +45,9 @@ class ContentsContainer : public views::View {
   void SetPreview(views::WebView* preview,
                   content::WebContents* preview_web_contents);
 
+  // Sets the desired height of the current preview view.
+  void SetPreviewHeight(int value, bool is_percent);
+
   content::WebContents* preview_web_contents() const {
     return preview_web_contents_;
   }
@@ -70,6 +73,10 @@ class ContentsContainer : public views::View {
   // preview overlap the bookmark bar on the new tab page.
   int active_top_margin_;
 
+  // The desired height of the preview. If negative or greater than height(),
+  // the preview will fill the container.
+  int preview_height_;
+
   DISALLOW_COPY_AND_ASSIGN(ContentsContainer);
 };