Add GetIsPinnedToTaskbarState()

chrome/browser/shell_integration_win.h

Index: chrome/browser/shell_integration_win.h
diff --git a/chrome/browser/shell_integration_win.h b/chrome/browser/shell_integration_win.h
index 3d81886fcd413aad42c34563885d70952cb7025f..4e7ce1bc894b5ea1909ddc7f2d0d57fdf1663af2 100644
--- a/chrome/browser/shell_integration_win.h
+++ b/chrome/browser/shell_integration_win.h
@@ -57,9 +57,15 @@ base::string16 GetAppModelIdForProfile(const base::string16& app_name,
 // calling GetAppModelIdForProfile() with ShellUtil::GetAppId() as app_name.
 base::string16 GetChromiumModelIdForProfile(const base::FilePath& profile_path);
 
-// Records the pinned state of the current executable into a histogram. Must be
-// called on the IO thread.
-void RecordIsPinnedToTaskbarHistogram();
+// Returns the taskbar pin state of Chrome via the IsPinnedToTaskbarCallback.
+// The first bool is true if the state could be calculated, and the second bool
+// is true if Chrome is pinned to the taskbar.
+// The ConnectionErrorCallback is called instead if something wrong happened
+// with the connection to the remote process.
+using ConnectionErrorCallback = base::Closure;
+using IsPinnedToTaskbarCallback = base::Callback<void(bool, bool)>;
+void GetIsPinnedToTaskbarState(ConnectionErrorCallback on_error_callback,

[grt (UTC plus 2), 2016/11/21 10:45:31]

does this need to be called on the IO thread? if so, please document as such. if
not, should the metrics code and/or comments be updated?

[grt (UTC plus 2), 2016/11/21 10:45:31]

nit: pass callbacks via constref everywhere

[Patrick Monette, 2016/11/21 18:48:47]

I don't think it does since it's not blocking IO. I've removed the DCHECK in
chrome_browser_main_extra_parts_metrics.cc

[Patrick Monette, 2016/11/21 18:48:47]

Done.

+                               IsPinnedToTaskbarCallback result_callback);
 
 // Migrates existing chrome taskbar pins by tagging them with correct app id.
 // see http://crbug.com/28104