Remove implementation of Panels on OSes other than ChromeOS.

chrome/browser/task_manager/web_contents_tags.h

Index: chrome/browser/task_manager/web_contents_tags.h
diff --git a/chrome/browser/task_manager/web_contents_tags.h b/chrome/browser/task_manager/web_contents_tags.h
index 4028173624d4d03d7d60b979430648453c6b92c6..8df36b04ecd61fc8d60f137123f31d734dd5028e 100644
--- a/chrome/browser/task_manager/web_contents_tags.h
+++ b/chrome/browser/task_manager/web_contents_tags.h
@@ -9,7 +9,6 @@
 #include "extensions/common/view_type.h"
 
 class BackgroundContents;
-class Panel;
 
 namespace content {
 class WebContents;
@@ -55,14 +54,6 @@ class WebContentsTags {
   // it is owned by |web_contents|.
   static void CreateForTabContents(content::WebContents* web_contents);
 
-  // Tag a WebContents owned by a |panel| in the PanelManager so that it shows
-  // up in the task manager. Calling this function creates a PanelTag, and
-  // attaches it to |web_contents|. If an instance is already attached, this
-  // does nothing. The resulting tag does not have to be cleaned up by the
-  // caller, as it is owned by |web_contents|.
-  // Note: |web_contents| must be equal to |panel->GetWebContents()|.
-  static void CreateForPanel(content::WebContents* web_contents, Panel* panel);
-
   // Tag a WebContents created for a print preview or background printing so
   // that it shows up in the task manager. Calling this function creates a
   // PrintingTag, and attaches it to |web_contents|. If an instance is already
@@ -82,7 +73,7 @@ class WebContentsTags {
   // it to |web_contents|. If an instance is already attached, this does
   // nothing. The resulting tag does not have to be cleaned up by the caller,
   // as it is owned by |web_contents|.
-  // |web_contents| must be of a non-tab, non-guest view, non-panel, or
+  // |web_contents| must be of a non-tab, non-guest view, or
   // non-background contents Extension.
   static void CreateForExtension(content::WebContents* web_contents,
                                  extensions::ViewType view_type);