Expose the selection root bounds in WebView.

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index bfa58740ba092e1c5f066fa3e5c83eb3814519c0..4245cb43b0380017598a0c5d87e5dcdf7dc0d1c3 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -2144,6 +2144,33 @@ bool WebViewImpl::selectionBounds(WebRect& anchor, WebRect& focus) const
     return true;
 }
 
+bool WebViewImpl::selectionRootBounds(WebRect& bounds) const
+{
+    const LocalFrame* frame = focusedWebCoreFrame();
+    if (!frame)
+        return false;
+
+    Element* root = frame->selection().rootEditableElementOrDocumentElement();
+    if (!root)
+        return false;
+
+    // If the selection is inside a form control, the root will be a <div> that

[timvolodine, 2014/03/06 17:02:02]

What about textarea elements? Could you list all cases here where the
root->shadowHost() is required?

[mlamouri (slow - plz ping), 2014/03/10 16:05:59]

Done.

+    // behaves as the editor but we want to return the actual element's bounds.
+    if (root->shadowHost()
+        && (root->shadowHost()->hasTagName(HTMLNames::textareaTag)
+            || (root->shadowHost()->hasTagName(HTMLNames::inputTag)
+                && toHTMLInputElement(root->shadowHost())->isText()))) {

[timvolodine, 2014/03/05 19:41:02]

no single-line brackets

[mlamouri (slow - plz ping), 2014/03/06 13:45:31]

Given the size of the condition, I think having brackets is fair.

[timvolodine, 2014/03/06 17:02:02]

I was actually referring to:
http://dev.chromium.org/blink/coding-style#TOC-Indentation, item5.
Yes the condition looks a bit heavy, maybe it makes sense to put
root->shadowHost() in a local variable to make it more compact and avoid
repetitions..

[mlamouri (slow - plz ping), 2014/03/10 16:05:59]

I fixed the brackets. Switching to root->shadowHost() to shadowHost
unfortunately doesn't make the condition more readable.

[timvolodine, 2014/03/10 17:50:00]

The more I look at this now the more I am for putting the root->shadowHost()
into a local variable. There are 5x root->shadowHost() calls which are not
completely trivial, so this will save some CPU work (in addition to making the
code more compact).

+        root = root->shadowHost();
+    }
+
+    IntRect boundingBox = root->pixelSnappedBoundingBox();
+    boundingBox = root->document().frame()->view()->contentsToWindow(boundingBox);
+    boundingBox.scale(pageScaleFactor());
+    bounds = boundingBox;
+
+    return true;
+}
+
 InputMethodContext* WebViewImpl::inputMethodContext()
 {
     if (!m_imeAcceptEvents)