docs(changelog): minor updates to 2.3.1 changelog

CHANGELOG.md

@@ -20,25 +20,20 @@
 * **compiler:** update to metadata version 3 ([#13464](https://github.com/angular/angular/issues/13464)) ([b9b557c](https://github.com/angular/angular/commit/b9b557c))
 * **core:** detectChanges() doesn't work on detached instance ([4d6ac9d](https://github.com/angular/angular/commit/4d6ac9d)), closes [#13426](https://github.com/angular/angular/issues/13426) [#13472](https://github.com/angular/angular/issues/13472)
 * **core:** properly destroy embedded Views attatched to ApplicationRef ([#13459](https://github.com/angular/angular/issues/13459)) ([d40bbf4](https://github.com/angular/angular/commit/d40bbf4)), closes [#13062](https://github.com/angular/angular/issues/13062)
-* **dom_adapter:** remove logError from logGroup ([#12925](https://github.com/angular/angular/issues/12925)) ([5fab871](https://github.com/angular/angular/commit/5fab871))
+* **core:** remove logError from logGroup ([#12925](https://github.com/angular/angular/issues/12925)) ([5fab871](https://github.com/angular/angular/commit/5fab871))
 * **forms:** ensure `select[multiple]` retains selections ([b3dcff0](https://github.com/angular/angular/commit/b3dcff0)), closes [#12527](https://github.com/angular/angular/issues/12527) [#12654](https://github.com/angular/angular/issues/12654)
 * **forms:** fix Validators.min/maxLength with FormArray ([#13095](https://github.com/angular/angular/issues/13095)) ([7383e4a](https://github.com/angular/angular/commit/7383e4a)), closes [#13089](https://github.com/angular/angular/issues/13089)
 * **forms:** introduce checkbox required validator ([124267c](https://github.com/angular/angular/commit/124267c)), closes [#11459](https://github.com/angular/angular/issues/11459) [#13364](https://github.com/angular/angular/issues/13364)
 * **http:** check response body text against undefined ([#13017](https://github.com/angular/angular/issues/13017)) ([f106a18](https://github.com/angular/angular/commit/f106a18))
 * **http:** create a copy of headers when merge options ([#13365](https://github.com/angular/angular/issues/13365)) ([65c9b5b](https://github.com/angular/angular/commit/65c9b5b)), closes [#11980](https://github.com/angular/angular/issues/11980)
 * **language-service:** correctly type `undefined` ([0a7364f](https://github.com/angular/angular/commit/0a7364f)), closes [#13412](https://github.com/angular/angular/issues/13412) [#13414](https://github.com/angular/angular/issues/13414)
-* Better error when directive not listed in NgModule.declarations ([b0cd514](https://github.com/angular/angular/commit/b0cd514))
-* Better instructions on running examples and their tests ([203cc7e](https://github.com/angular/angular/commit/203cc7e))
+* **compiler**: better error when directive not listed in NgModule.declarations ([b0cd514](https://github.com/angular/angular/commit/b0cd514))
 * **language-service:** treat string unions as strings ([#13406](https://github.com/angular/angular/issues/13406)) ([14dd2b3](https://github.com/angular/angular/commit/14dd2b3)), closes [#13403](https://github.com/angular/angular/issues/13403)
 * **router:** add support for query params with multiple values ([e4d5a5f](https://github.com/angular/angular/commit/e4d5a5f)), closes [#11373](https://github.com/angular/angular/issues/11373)
 * **router:** Use T type in Resolve interface ([#13242](https://github.com/angular/angular/issues/13242)) ([5ee8155](https://github.com/angular/angular/commit/5ee8155))
 * **selector:** SelectorMatcher match elements with :not selector ([#12977](https://github.com/angular/angular/issues/12977)) ([392c9ac](https://github.com/angular/angular/commit/392c9ac))
 * **tsc-wrapped:** generate metadata for exports without module specifier ([cd03c77](https://github.com/angular/angular/commit/cd03c77)), closes [#13327](https://github.com/angular/angular/issues/13327)
 * **upgrade:** fix downgrade content projection and injector inheritance ([86c5098](https://github.com/angular/angular/commit/86c5098)), closes [#6629](https://github.com/angular/angular/issues/6629) [#7727](https://github.com/angular/angular/issues/7727) [#8729](https://github.com/angular/angular/issues/8729) [#9643](https://github.com/angular/angular/issues/9643) [#9649](https://github.com/angular/angular/issues/9649) [#12675](https://github.com/angular/angular/issues/12675)
-
-
-### Features
-
 * **upgrade:** enable Angular 1 unit testing of upgrade module ([2fc0560](https://github.com/angular/angular/commit/2fc0560)), closes [#5462](https://github.com/angular/angular/issues/5462) [#12675](https://github.com/angular/angular/issues/12675)
 
 
@@ -46,6 +41,16 @@
 
 * **animations:** always run the animation queue outside of zones ([e2622ad](https://github.com/angular/angular/commit/e2622ad)), closes [#13440](https://github.com/angular/angular/issues/13440)
 
+### Note ###
+
+Due to regression in the 2.3.0 release that was fixed by [#13464](https://github.com/angular/angular/pull/13464), 
+components that have been compiled using 2.3.0 and published to npm will need to be recompiled and republished.
+
+The >=2.3.1 compiler will issue is the following error if it encounters components compiled with 2.3.0:  
+`Unsupported metadata version 2 for module ${module}. This module should be compiled with a newer version of ngc`.
+
+We are adding more tests to our test suite to catch these kinds of problems before we cut a release.
+
 
 <a name="2.3.0"></a>
 # [2.3.0](https://github.com/angular/angular/compare/2.3.0-rc.0...2.3.0) (2016-12-07)