This CL fixes issue 17468 - Regression: Extra white rectangle showing when mouse hovering on every web page

Should check tooltip text against empty before adding Unicode Marks for directionality.

BUG=http://crbug.com/17468
BUG=http://crbug.com/17176
BUG=http://crbug.com/5996
TEST= open a webpage, mouse over plain text area, empty square should not show up as tooltip. 
Review URL: http://codereview.chromium.org/159222

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21353 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 10 insertions, 8 deletions

diff --git a/webkit/glue/chrome_client_impl.cc b/webkit/glue/chrome_client_impl.cc
index ac1866f..fa965ef 100644
--- a/webkit/glue/chrome_client_impl.cc
+++ b/webkit/glue/chrome_client_impl.cc
@@ -517,14 +517,16 @@ void ChromeClientImpl::setToolTip(const WebCore::String& tooltip_text,
   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);
-    } 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);
+    if (!tooltip_text_as_wstring.empty()) {
+      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);
+      } 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);
   }