add release note about linker deprecation

Change-Id: Iffecd275ae13737baed21b5673c5ce896d820808
diff --git a/src/main/markdown/release-notes.md b/src/main/markdown/release-notes.md
index cb0c316..42c7a91 100644
--- a/src/main/markdown/release-notes.md
+++ b/src/main/markdown/release-notes.md
@@ -73,6 +73,17 @@
 
 - gwttar files are incorrect. (Fixed in the next version)
 
+<h3>Deprecations</h3>
+
+- GWT Designer doesn't work with 2.7 and is no longer supported.
+([Source code](https://code.google.com/p/gwt-designer/) is available
+if someone wishes to revive this project.)
+
+- IFrameLinker and XSLinker are deprecated because they don't work in
+Super Dev Mode. However, we don't have suitable replacements for all
+use cases yet. For updates and possible workarounds, see
+[issue 8997](https://code.google.com/p/google-web-toolkit/issues/detail?id=8997).
+
 <h3>Compiler changes</h3>
 
 - In draft mode and Super Dev Mode, all compiler optimizations are turned off for
@@ -99,10 +110,6 @@
 
 - Many bugfixes.
 
-<h3>Deprecations</h3>
-
-- GWT Designer doesn't work and is no longer supported.
-
 <h3>Library Changes</h3>
 
 <h4>JDK emulation</h4>