release: v0.52.0

This PR will be tagged v0.52.0.

Change-Id: I1aa853cf1d439f4796733ca891f56d9033f729ff
Reviewed-on: https://code-review.googlesource.com/c/gocloud/+/50711
Reviewed-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Tyler Bui-Palsulich <tbp@google.com>
diff --git a/CHANGES.md b/CHANGES.md
index 82e0db4..8dba920 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,12 @@
 # Changes
 
+## v0.52.0
+
+- internal/gapicgen: multiple improvements related to library generation.
+- compute/metadata: unset ResponseHeaderTimeout in defaultClient
+- docs: fix link to KMS in README.md
+- Various updates to autogenerated clients.
+
 ## v0.51.0
 
 - secretmanager:
diff --git a/internal/version/version.go b/internal/version/version.go
index 84eff70..1c49664 100644
--- a/internal/version/version.go
+++ b/internal/version/version.go
@@ -26,7 +26,7 @@
 
 // Repo is the current version of the client libraries in this
 // repo. It should be a date in YYYYMMDD format.
-const Repo = "20200107"
+const Repo = "20200122"
 
 // Go returns the Go runtime version. The returned string
 // has no whitespace.