Revert of Remove unnecessary spin in ToolTipController

ui/views/corewm/tooltip_controller.cc

Index: ui/views/corewm/tooltip_controller.cc
diff --git a/ui/views/corewm/tooltip_controller.cc b/ui/views/corewm/tooltip_controller.cc
index 299a039ec42c7102218378b7672ccae94c19a066..cd1792ffa29d03692804fa4162d8a450adcb171c 100644
--- a/ui/views/corewm/tooltip_controller.cc
+++ b/ui/views/corewm/tooltip_controller.cc
@@ -25,12 +25,12 @@
 #include "ui/gfx/text_elider.h"
 #include "ui/views/corewm/tooltip.h"
 #include "ui/views/widget/tooltip_manager.h"
-#include "ui/wm/public/tooltip_client.h"
 
 namespace views {
 namespace corewm {
 namespace {
 
+const int kTooltipTimeoutMs = 500;
 const int kDefaultTooltipShownTimeoutMs = 10000;
 #if defined(OS_WIN)
 // Drawing a long word in tooltip is very slow on Windows. crbug.com/513693
@@ -129,7 +129,11 @@
       tooltip_id_(NULL),
       tooltip_window_at_mouse_press_(NULL),
       tooltip_(std::move(tooltip)),
-      tooltips_enabled_(true) {}
+      tooltips_enabled_(true) {
+  tooltip_timer_.Start(FROM_HERE,
+      base::TimeDelta::FromMilliseconds(kTooltipTimeoutMs),
+      this, &TooltipController::TooltipTimerFired);
+}
 
 TooltipController::~TooltipController() {
   if (tooltip_window_)
@@ -146,13 +150,26 @@
     UpdateIfRequired();
 
   // Reset |tooltip_window_at_mouse_press_| if the moving within the same window
-  // but over a region that has different tooltip text.
+  // but over a region that has different tooltip text. By resetting
+  // |tooltip_window_at_mouse_press_| we ensure the next time the timer fires
+  // we'll requery for the tooltip text.
   // This handles the case of clicking on a view, moving within the same window
   // but over a different view, than back to the original.
   if (tooltip_window_at_mouse_press_ &&
       target == tooltip_window_at_mouse_press_ &&
       aura::client::GetTooltipText(target) != tooltip_text_at_mouse_press_) {
     tooltip_window_at_mouse_press_ = NULL;
+  }
+
+  // If we had stopped the tooltip timer for some reason, we must restart it if
+  // there is a change in the tooltip.
+  if (!tooltip_timer_.IsRunning()) {
+    if (tooltip_window_ != target || (tooltip_window_ &&
+        tooltip_text_ != aura::client::GetTooltipText(tooltip_window_))) {
+      tooltip_timer_.Start(FROM_HERE,
+          base::TimeDelta::FromMilliseconds(kTooltipTimeoutMs),
+          this, &TooltipController::TooltipTimerFired);
+    }
   }
 }
 
@@ -194,10 +211,10 @@
         target = GetTooltipTarget(*event, &curr_mouse_loc_);
       }
       SetTooltipWindow(target);
-
-      if (tooltip_->IsVisible() ||
-          (tooltip_window_ &&
-           tooltip_text_ != aura::client::GetTooltipText(tooltip_window_)))
+      if (tooltip_timer_.IsRunning())
+        tooltip_timer_.Reset();
+
+      if (tooltip_->IsVisible())
         UpdateIfRequired();
       break;
     }
@@ -215,6 +232,10 @@
       // Hide the tooltip for click, release, drag, wheel events.
       if (tooltip_->IsVisible())
         tooltip_->Hide();
+
+      // Don't reshow the tooltip during scroll.
+      if (tooltip_timer_.IsRunning())
+        tooltip_timer_.Reset();
       break;
     default:
       break;
@@ -234,10 +255,6 @@
   SetTooltipWindow(NULL);
 }
 
-void TooltipController::OnCursorVisibilityChanged(bool is_visible) {
-  UpdateIfRequired();
-}
-
 void TooltipController::OnWindowDestroyed(aura::Window* window) {
   if (tooltip_window_ == window) {
     tooltip_->Hide();
@@ -246,22 +263,20 @@
   }
 }
 
-void TooltipController::OnWindowPropertyChanged(aura::Window* window,
-                                                const void* key,
-                                                intptr_t old) {
-  if ((key == aura::client::kTooltipIdKey ||
-       key == aura::client::kTooltipTextKey) &&
-      aura::client::GetTooltipText(window) != base::string16() &&
-      (tooltip_text_ != aura::client::GetTooltipText(window) ||
-       tooltip_id_ != aura::client::GetTooltipId(window)))
-    UpdateIfRequired();
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // TooltipController private:
 
+void TooltipController::TooltipTimerFired() {
+  UpdateIfRequired();
+}
+
 void TooltipController::TooltipShownTimerFired() {
   tooltip_->Hide();
+
+  // Since the user presumably no longer needs the tooltip, we also stop the
+  // tooltip timer so that tooltip does not pop back up. We will restart this
+  // timer if the tooltip changes (see UpdateTooltip()).
+  tooltip_timer_.Stop();
 }
 
 void TooltipController::UpdateIfRequired() {
@@ -294,6 +309,9 @@
   ids_differ = tooltip_id_ != tooltip_id;
   tooltip_id_ = tooltip_id;
 
+  // We add the !tooltip_->IsVisible() below because when we come here from
+  // TooltipTimerFired(), the tooltip_text may not have changed but we still
+  // want to update the tooltip because the timer has fired.
   // If we come here from UpdateTooltip(), we have already checked for tooltip
   // visibility and this check below will have no effect.
   if (tooltip_text_ != tooltip_text || !tooltip_->IsVisible() || ids_differ) {