Review Request: display tooltip in the directionality of its element's

webkit/glue/chrome_client_impl.cc

Index: webkit/glue/chrome_client_impl.cc
===================================================================
--- webkit/glue/chrome_client_impl.cc	(revision 19223)
+++ webkit/glue/chrome_client_impl.cc	(working copy)
@@ -9,6 +9,7 @@
 MSVC_PUSH_WARNING_LEVEL(0);
 #include "AccessibilityObject.h"
 #include "AXObjectCache.h"
+#include "CharacterNames.h"
 #include "Console.h"
 #include "Cursor.h"
 #include "Document.h"
@@ -504,10 +505,20 @@
   }
 }
 
-void ChromeClientImpl::setToolTip(const WebCore::String& tooltip_text) {
+void ChromeClientImpl::setToolTip(const WebCore::String& tooltip_text,
+                                  WebCore::TextDirection dir) {
   if (webview_->delegate()) {
     std::wstring tooltip_text_as_wstring =
       webkit_glue::StringToStdWString(tooltip_text);
+    if (dir == WebCore::LTR) {
+      // Force the tooltip to have LTR directionality.
+      tooltip_text_as_wstring.insert(0, 1, WebCore::leftToRightEmbed);
+      tooltip_text_as_wstring.push_back(WebCore::popDirectionalFormatting);

[idana, 2009/07/20 20:50:10]

Are you sure that it is safe to insert these characters when the directionality
is LTR?

I know that, originally, I was very careful not to insert directionality
characters when the Chrome UI language was not RTL because it Windows doesn't
know how to handle these characters if the right to left fonts are not
installed. You can test that on an XP box by making sure the fonts are
un-installed before you run Chrome.

[jungshik at Google, 2009/07/20 21:18:33]

It's whether or not 'install files for complex script and rtl languages
(including Thai)' is checked  in Control panel - regional and language settings
- language tab. 

If it's indeed a problem without that checked on XP, we have to figure out how
to tell whether that's checked or not and do things differently depending on the
result. 

BTW, is this code cross-platform? If so, we have to check on Mac and Linux, too
although it's likely to be ok there. 

[xji, 2009/07/20 23:51:04]

I unchecked "install files for complex script and rtl languages (including
thai)" and reboot my XP,
the above change works fine for both Hebrew and English Chrome. Unicode marks
did not cause any problem, and the tooltip are displayed with expected
directionality.

+    } else {
+      // Force the tooltip to have RTL directionality.
+      tooltip_text_as_wstring.insert(0, 1, WebCore::rightToLeftEmbed);
+      tooltip_text_as_wstring.push_back(WebCore::popDirectionalFormatting);
+    }
     webview_->delegate()->SetTooltipText(webview_, tooltip_text_as_wstring);
   }
 }