Fix crash when trying to iterate over words in an inline text box of length zero.

Source/core/rendering/AbstractInlineTextBox.cpp

Index: Source/core/rendering/AbstractInlineTextBox.cpp
diff --git a/Source/core/rendering/AbstractInlineTextBox.cpp b/Source/core/rendering/AbstractInlineTextBox.cpp
index becc7cfbdff3b10b01113e25d1aa2b70def91fde..058280d7311df08ccb7fa53cd1c5f0fa9f0a48df 100644
--- a/Source/core/rendering/AbstractInlineTextBox.cpp
+++ b/Source/core/rendering/AbstractInlineTextBox.cpp
@@ -131,6 +131,9 @@ void AbstractInlineTextBox::wordBoundaries(Vector<WordBoundaries>& words) const
 
     String text = this->text();
     int len = text.length();
+    if (!len)

[eseidel, 2014/09/04 16:39:49]

Should this be moved to after wordBreakIterator if (iterator) instead?

[dmazzoni, 2014/09/04 16:46:57]

Sure. I was torn between catching the actual crash (null iterator) or the
underlying reason behind it (len == 0). I switched it to check the iterator but
added a comment so we know there's a reason why it might happen.

+        return;
+
     TextBreakIterator* iterator = wordBreakIterator(text, 0, len);
     int pos = iterator->first();
     while (pos >= 0 && pos < len) {