Migrate HostZoomMap to live in StoragePartition.

content/shell/browser/shell_browser_context.h

Index: content/shell/browser/shell_browser_context.h
diff --git a/content/shell/browser/shell_browser_context.h b/content/shell/browser/shell_browser_context.h
index d4e146fbf4e51acd3c33d1bb33b3e10de1609e55..2162ea0f881052d262338080852db20f70725c97 100644
--- a/content/shell/browser/shell_browser_context.h
+++ b/content/shell/browser/shell_browser_context.h
@@ -23,6 +23,7 @@ namespace content {
 
 class DownloadManagerDelegate;
 class ShellDownloadManagerDelegate;
+class ZoomLevelDelegate;
 
 class ShellBrowserContext : public BrowserContext {
  public:
@@ -36,6 +37,8 @@ class ShellBrowserContext : public BrowserContext {
 
   // BrowserContext implementation.
   base::FilePath GetPath() const override;
+  scoped_ptr<ZoomLevelDelegate> CreateZoomLevelDelegate(
+      const base::FilePath& partition_path) override;
   bool IsOffTheRecord() const override;
   DownloadManagerDelegate* GetDownloadManagerDelegate() override;
   net::URLRequestContextGetter* GetRequestContext() override;