Update the %diff modifer to have an alternate string print when a template tree
is selected.  This will allow more flexibility when converting diagnostics to
use template type diffing.

Also updated the internal manual and test cases for correctly keeping the bold
attribute and for tree printing.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159463 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/InternalsManual.html b/docs/InternalsManual.html
index 76b0c67..6a67368 100644
--- a/docs/InternalsManual.html
+++ b/docs/InternalsManual.html
@@ -361,7 +361,8 @@
 <tr><td colspan="2"><b>"diff" format</b></td></tr>
 <tr><td>Example:</td><td><tt>"no known conversion %diff{from | to | }1,2"</tt></td></tr>
 <tr><td>Class:</td><td>QualType</td></tr>
-<tr><td>Description</td><td><p>This formatter takes two QualTypes and attempts to print a template difference between the two.  If tree printing is off, the entire text inside the the braces is printed, with the formatted text replacing the pipes.  If tree printing is on, the text is not printed and a type tree is printed after the diagnostic message.</p></td></tr>
+<tr><td>Description</td><td><p>This formatter takes two QualTypes and attempts to print a template difference between the two.  If tree printing is off, the text inside the the braces before the pipe is printed, with the formatted text replacing the $.  If tree printing is on, the text after the pipe is printed and a type tree is printed after the diagnostic message.
+</p></td></tr>
     
 </table>