Remove mail blockquote special case handling.

LayoutTests/editing/pasteboard/4922709.html

Index: LayoutTests/editing/pasteboard/4922709.html
diff --git a/LayoutTests/editing/pasteboard/4922709.html b/LayoutTests/editing/pasteboard/4922709.html
deleted file mode 100644
index 88f9f74d49a391af0d0f9169e17d64c0180b6cc9..0000000000000000000000000000000000000000
--- a/LayoutTests/editing/pasteboard/4922709.html
+++ /dev/null
@@ -1,31 +0,0 @@
-<style>
-blockquote {
-    border-left: 2px solid blue;
-    margin: 0;
-    padding-left: 10px;
-    color: blue;
-}
-</style>
-<div id="description">This tests copying/pasting less than a paragraph of quoted content.  It should appear quoted.</div>
-<div id="edit" contenteditable="true">
-<br>
-<br>
-<div>On Tuesday, Dave wrote:</div>
-<div><br></div>
-<blockquote id="blockquote" type="cite">Hello World</blockquote>
-</div>
-
-<script>
-if (window.testRunner)
-    window.testRunner.dumpAsText();
-blockquote = document.getElementById("blockquote");
-text = blockquote.firstChild;
-sel = window.getSelection();
-sel.setBaseAndExtent(text, 0, text, text.length);
-document.execCommand("Copy");
-edit = document.getElementById("edit");
-sel.setPosition(edit, 0);
-document.execCommand("Paste");
-if (window.testRunner)
-    document.body.innerText = document.getElementById("description").innerText + "\n\n" + document.getElementById("edit").innerHTML;
-</script>