Remove force stacking when touchable chrome is enabled

This patch removes the force stacking of tabs when touch optimized
chrome is enabled and restores the old approach.

Bug: 844193
Change-Id: Icf591860d06afe4698817291f70d619343237a82
Component: Touchable chrome, tabstrip, tab stacking
Reviewed-on: https://chromium-review.googlesource.com/1066864
Commit-Queue: Malay Keshav <malaykeshav@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560292}

chrome/browser/ui/views/tabs/browser_tab_strip_controller.cc

@@ -66,9 +66,7 @@ bool DetermineTabStripLayoutStacked(PrefService* prefs, bool* adjust_layout) {
   // For ash, always allow entering stacked mode.
 #if defined(OS_CHROMEOS)
   *adjust_layout = true;
-  // Stacked layout is always enabled in touch optimized UI design.
-  return ui::MaterialDesignController::IsTouchOptimizedUiEnabled() ||
-         prefs->GetBoolean(prefs::kTabStripStackedLayout);
+  return prefs->GetBoolean(prefs::kTabStripStackedLayout);
 #else
   return base::CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kForceStackedTabStripLayout);

chrome/browser/ui/views/tabs/tab_strip.cc

@@ -2389,9 +2389,8 @@ bool TabStrip::NeedsTouchLayout() const {
 }
 
 void TabStrip::SetResetToShrinkOnExit(bool value) {
-  if (!adjust_layout_ || MD::IsTouchOptimizedUiEnabled()) {
+  if (!adjust_layout_)
     return;
-  }
 
   // We have to be using stacked layout to reset out of it.
   value &= stacked_layout_;