Add heuristics to limit showing of new backspace UI bubble.

chrome/browser/ui/browser_view_prefs.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/browser_view_prefs.h"
 
 #include "build/build_config.h"
 #include "chrome/common/pref_names.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/prefs/pref_registry_simple.h"
@@ skipping 12 matching lines @@
 
 }  // namespace
 
 namespace chrome {
 
 void RegisterBrowserViewLocalPrefs(PrefRegistrySimple* registry) {
   registry->RegisterIntegerPref(kTabStripLayoutType, 0);
   registry->RegisterBooleanPref(prefs::kTabStripStackedLayout, false);
 }
 
 void RegisterBrowserViewProfilePrefs(

[Matt Giuca, 2016/06/08 01:29:03]

Just to be clear (for my own benefit): this means it is a per-profile pref, yes?
So each user will get their own 5 shows. (That's implied by the name but I
thought I'd check.)

Also I assume these are unsynced prefs.

Both of those are fine. (Unsynced is probably a good thing because if a user has
a Windows PC and a Mac PC we can train them on the different shortcuts.)

[Peter Kasting, 2016/06/09 19:49:31]

Yes.
It's not synced here, but in thinking about it, I think syncing is the right
thing.

You're correct that users with different platforms will have slightly different
shortcuts, but the differences aren't very significant.  And I suspect the
common case is that people use the same platform.  I'd rather err on the side of
not annoying people.

So, making this syncable.

[Matt Giuca, 2016/06/10 01:07:05]

Acknowledged.

     user_prefs::PrefRegistrySyncable* registry) {
   bool custom_frame_default = false;
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
   custom_frame_default = ui::GetCustomFramePrefDefault();
 #endif
-
   registry->RegisterBooleanPref(prefs::kUseCustomChromeFrame,

[Matt Giuca, 2016/06/08 01:29:03]

nit: Any reason to delete the above line? If anything I think there should be a
blank line here but none between the two Register*Pref calls.

[Peter Kasting, 2016/06/09 19:49:31]

The code above is closely tied to this line: it's calculating the value to pass
to this function.  If we didn't need an ifdef, we'd have inlined that code into
this call.

Whereas this call and the one below have no relationship to each other; they're
for different prefs with different values.

[Matt Giuca, 2016/06/10 01:07:05]

Acknowledged.

                                 custom_frame_default);
+
+  registry->RegisterIntegerPref(prefs::kBackShortcutBubbleShownCount, 0);

[Matt Giuca, 2016/06/08 01:29:03]

I think we should have separate counters for the Back and Forward shortcuts.
Otherwise you could use up your 5 Back presses and never be taught the Forward
shortcut.

[Peter Kasting, 2016/06/09 19:49:31]

My instinct is that one counter for both is the way to go.

I asked Tyler to weigh in.  He also thought one counter would be best, noting
that the forward shortcut is pretty intuitive once one knows the back shortcut.

Neither of us feel violently about this, if you want to try to convince us
further.

[Matt Giuca, 2016/06/10 01:07:05]

Not particularly :)

 }
 
 void MigrateBrowserTabStripPrefs(PrefService* prefs) {
   if (prefs->HasPrefPath(kTabStripLayoutType)) {
     prefs->SetBoolean(prefs::kTabStripStackedLayout,
                       prefs->GetInteger(kTabStripLayoutType) != 0);
     prefs->ClearPref(kTabStripLayoutType);
   }
 }
 
 }  // namespace chrome