Bug 1213845 - enable osk support on windows 8, but hide it behind a preference, r=jaws

--HG--
extra : commitid : HGvNNv1htDF
extra : rebase_source : 7c39d7903bfda6040a202d6784c5a4e469a7eeed
extra : amend_source : af5a54a5fe9f3120c30dfe6ac3b607da596364e9

modules/libpref/init/all.js

@@ -3268,9 +3268,9 @@ pref("ui.osk.enabled", true);
 pref("ui.osk.detect_physical_keyboard", true);
 // Path to TabTip.exe on local machine. Cached for performance reasons.
 pref("ui.osk.on_screen_keyboard_path", "");
-// Only show the on-screen keyboard when Windows is in Tablet mode. Setting
+// Only try to show the on-screen keyboard on Windows 10 and later. Setting
-// this pref to false will allow the OSK to show in regular non-tablet mode.
+// this pref to false will allow the OSK to show on Windows 8 and 8.1.
-pref("ui.osk.require_tablet_mode", true);
+pref("ui.osk.require_win10", false);
 // This pref stores the "reason" that the on-screen keyboard was either
 // shown or not shown when focus is moved to an editable text field. It is
 // used to help debug why the keyboard is either not appearing when expected

widget/windows/WinIMEHandler.cpp

@@ -28,7 +28,7 @@
 const char* kOskPathPrefName = "ui.osk.on_screen_keyboard_path";
 const char* kOskEnabled = "ui.osk.enabled";
 const char* kOskDetectPhysicalKeyboard = "ui.osk.detect_physical_keyboard";
-const char* kOskRequireTabletMode = "ui.osk.require_tablet_mode";
+const char* kOskRequireWin10 = "ui.osk.require_win10";
 const char* kOskDebugReason = "ui.osk.debug.keyboardDisplayReason";
 
 namespace mozilla {
@@ -539,21 +539,22 @@ void
 IMEHandler::MaybeShowOnScreenKeyboard()
 {
   if (sPluginHasFocus ||
-      !IsWin10OrLater() ||
+      !IsWin8OrLater() ||
       !Preferences::GetBool(kOskEnabled, true) ||
       sShowingOnScreenKeyboard ||
       IMEHandler::IsKeyboardPresentOnSlate()) {
     return;
   }
 
-  // Tablet Mode is only supported on Windows 10 and higher.
+  // On Windows 10 we require tablet mode, unless the user has set the relevant
-  // When touch-event detection within IME is better supported
+  // Windows setting to enable the on-screen keyboard in desktop mode.
-  // this check may be removed, and ShowOnScreenKeyboard can
+  // We might be disabled specifically on Win8(.1), so we check that afterwards.
-  // run on Windows 8 and higher (adjusting the IsWin10OrLater
+  if (IsWin10OrLater()) {
-  // guard above and within MaybeDismissOnScreenKeyboard).
+    if (!IsInTabletMode() && !AutoInvokeOnScreenKeyboardInDesktopMode()) {
-  if (!IsInTabletMode() &&
+      return;
-      Preferences::GetBool(kOskRequireTabletMode, true) &&
+    }
-      !AutoInvokeOnScreenKeyboardInDesktopMode()) {
+  }
+  else if (Preferences::GetBool(kOskRequireWin10, true)) {
     return;
   }
 
@@ -565,7 +566,7 @@ void
 IMEHandler::MaybeDismissOnScreenKeyboard()
 {
   if (sPluginHasFocus ||
-      !IsWin10OrLater() ||
+      !IsWin8OrLater() ||
       !sShowingOnScreenKeyboard) {
     return;
   }