[Editing][BugFix] Fix if condition in ReplaceSelectionCommand

third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp

Index: third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp
diff --git a/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp b/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp
index 5eef8486a3ba1f1926a0aaf780173a5a5a686a53..5add5329865fd6ba67eda705e647cb0efc4247c8 100644
--- a/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp
+++ b/third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp
@@ -1013,10 +1013,11 @@ void ReplaceSelectionCommand::doApply()
         applyCommandToComposite(BreakBlockquoteCommand::create(document()));
         // This will leave a br between the split.
         Node* br = endingSelection().start().anchorNode();
-        ASSERT(isHTMLBRElement(br));
-        // Insert content between the two blockquotes, but remove the br (since it was just a placeholder).
-        insertionPos = positionInParentBeforeNode(*br);
-        removeNode(br);
+        if (isHTMLBRElement(br)) {

[yosin_UTC9, 2015/10/15 05:57:18]

It seems this can fix issue 541402 too. However, issue 541402, root cause
of this assertion failure is different. Can we make BreakBlockquoteCommand
always to insert BR?

What BreakBlockquoteCommand fail to insert BR?

+            // Insert content between the two blockquotes, but remove the br (since it was just a placeholder).
+            insertionPos = positionInParentBeforeNode(*br);
+            removeNode(br);
+        }
     }
 
     // Inserting content could cause whitespace to collapse, e.g. inserting <div>foo</div> into hello^ world.