[NaCl SDK] Cleanup references to old newlib toolchain

native_client_sdk/src/doc/sdk/release-notes.rst

Index: native_client_sdk/src/doc/sdk/release-notes.rst
diff --git a/native_client_sdk/src/doc/sdk/release-notes.rst b/native_client_sdk/src/doc/sdk/release-notes.rst
index 460d7237f3bf56fe25950ac1b881a0b7ef236cc7..d3bc83efe043eed5b2ea79a4cc55c79502cadc86 100644
--- a/native_client_sdk/src/doc/sdk/release-notes.rst
+++ b/native_client_sdk/src/doc/sdk/release-notes.rst
@@ -10,12 +10,15 @@ reached canary status. The stable release is typically 6 weeks later.
 Chrome/Pepper 49
 ================
 
-* gtest/gmock no longer shipped as prebuilt libraries.  This is in-line with
+* GCC-based newlib toolchains removed from the SDK.  These have been
+  superseded by the nacl-clang toolchain which also produces statically linked
+  architecture specific nexe files.
+* gtest/gmock no longer shipped as pre-built libraries.  This is in-line with
   normal gtest/gmock usage guidelines.  Projects wishing to use gtest/gmock must
-  now add explict include paths and compile gtest-all.cc locally.
+  now add explicit include paths and compile gtest-all.cc locally.
 
 Chrome/Pepper 45 (10 July 2015)
-================================
+===============================
 
 Pepper
 ------