Use FrameSelection::selectedText where possible.

third_party/WebKit/Source/core/editing/FrameSelection.cpp

Index: third_party/WebKit/Source/core/editing/FrameSelection.cpp
diff --git a/third_party/WebKit/Source/core/editing/FrameSelection.cpp b/third_party/WebKit/Source/core/editing/FrameSelection.cpp
index 92dd256df027e44a2e9287c4f38f813934812ae8..fa21187532457bb9aa2decb813dba51890fb35c1 100644
--- a/third_party/WebKit/Source/core/editing/FrameSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/FrameSelection.cpp
@@ -1101,6 +1101,8 @@ template <typename Strategy>
 String extractSelectedTextAlgorithm(const FrameSelection& selection, TextIteratorBehavior behavior)
 {
     const VisibleSelectionTemplate<Strategy> visibleSelection = selection.visibleSelection<Strategy>();
+    if (!visibleSelection.isRange())

[yosin_UTC9, 2015/10/06 05:41:51]

I think it is easier to make |normalizeRange()| to handle null range case
rather than each call site.

[kotenkov, 2015/10/06 12:29:23]

Actually, now the problem is not in |normalizeRange()| but in |createMarkup()|
-- it is not supposed to handle null position and I'm not sure whether we should
change this behavior. The check here is just for symmetry with
|extractSelectedHTMLAlgorithm()|, |plainText()| can handle empty ranges.

[yosin_UTC9, 2015/10/15 07:45:46]

Let's make both |normalizeRange()| and |createMarkup()| to handle null
range case to avoid null check on each call site.

+        return String();
     const EphemeralRangeTemplate<Strategy> range = visibleSelection.toNormalizedEphemeralRange();
     // We remove '\0' characters because they are not visibly rendered to the user.
     return plainText(range, behavior).replace(0, "");
@@ -1117,6 +1119,8 @@ template <typename Strategy>
 static String extractSelectedHTMLAlgorithm(const FrameSelection& selection)
 {
     const VisibleSelectionTemplate<Strategy> visibleSelection = selection.visibleSelection<Strategy>();
+    if (!visibleSelection.isRange())
+        return String();
     const EphemeralRangeTemplate<Strategy> range = visibleSelection.toNormalizedEphemeralRange();
     return createMarkup(range.startPosition(), range.endPosition(), AnnotateForInterchange, ConvertBlocksToInlines::NotConvert, ResolveNonLocalURLs);
 }
@@ -1128,9 +1132,9 @@ String FrameSelection::selectedHTMLForClipboard() const
     return extractSelectedHTMLAlgorithm<EditingInComposedTreeStrategy>(*this);
 }
 
-String FrameSelection::selectedText() const
+String FrameSelection::selectedText(TextIteratorBehavior behavior) const
 {
-    return extractSelectedText(*this, TextIteratorDefaultBehavior);
+    return extractSelectedText(*this, behavior);
 }
 
 String FrameSelection::selectedTextForClipboard() const