Remove redundant selection judge from EmbeddedContentPainter

EmbeddedContentPainter::IsSelected() is used to decide if paint 
 selection or not.
This function is strange because it refers selection_start/end.
That's because seletion_start/end means offset in the layout object
 and since replaced element neither be text nor have child 
LayoutObject.
Thus we should just consider SelectionState is kNone or not.

Bug: 739062
Change-Id: I249d8c2acef959ad437f3a636a490f42b61270e0
Reviewed-on: https://chromium-review.googlesource.com/575126Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Yoichi Osato <yoichio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#488109}

third_party/WebKit/Source/core/paint/EmbeddedContentPainter.cpp

@@ -23,25 +23,8 @@ bool EmbeddedContentPainter::IsSelected() const {
   SelectionState s = layout_embedded_content_.GetSelectionState();
   if (s == SelectionState::kNone)
     return false;
-  if (s == SelectionState::kInside)
-    return true;
-
-  int selection_start, selection_end;
-  std::tie(selection_start, selection_end) =
-      layout_embedded_content_.SelectionStartEnd();
-  if (s == SelectionState::kStart)
-    return selection_start == 0;
-
-  int end = layout_embedded_content_.GetNode()->hasChildren()
-                ? layout_embedded_content_.GetNode()->CountChildren()
-                : 1;
-  if (s == SelectionState::kEnd)
-    return selection_end == end;
-  if (s == SelectionState::kStartAndEnd)
-    return selection_start == 0 && selection_end == end;
-
-  DCHECK(0);
-  return false;
+
+  return true;
 }
 
 void EmbeddedContentPainter::Paint(const PaintInfo& paint_info,