changelog: update to reflect 0.34.9 (#6334)

CHANGELOG.md

@@ -1,5 +1,34 @@
 # Changelog
 
+## v0.34.9
+
+*April 8, 2021*
+
+This release fixes a moderate severity security issue, Security Advisory Alderfly, 
+which impacts all networks that rely on Tendermint light clients.
+Further details will be released once networks have upgraded.
+
+This release also includes a small Go API-breaking change, to reduce panics in the RPC layer.
+
+Special thanks to our external contributors on this release: @gchaincl
+
+Friendly reminder: We have a [bug bounty program](https://hackerone.com/tendermint).
+
+### BREAKING CHANGES
+
+- Go API
+    - [rpc/jsonrpc/server] [\#6204](https://github.com/tendermint/tendermint/issues/6204) Modify `WriteRPCResponseHTTP(Error)` to return an error (@melekes)
+
+### FEATURES
+
+- [rpc] [\#6226](https://github.com/tendermint/tendermint/issues/6226) Index block events and expose a new RPC method, `/block_search`, to allow querying for blocks by `BeginBlock` and `EndBlock` events (@alexanderbez)
+
+### BUG FIXES
+
+- [rpc/jsonrpc/server] [\#6191](https://github.com/tendermint/tendermint/issues/6191) Correctly unmarshal `RPCRequest` when data is `null` (@melekes)
+- [p2p] [\#6289](https://github.com/tendermint/tendermint/issues/6289) Fix "unknown channels" bug on CustomReactors (@gchaincl)
+- [light/evidence] Adds logic to handle forward lunatic attacks (@cmwaters)
+
 ## v0.34.8
 
 *February 25, 2021*

CHANGELOG_PENDING.md

@@ -43,7 +43,6 @@ Friendly reminder: We have a [bug bounty program](https://hackerone.com/tendermi
   - [rpc/client/http] \#6176 Remove `endpoint` arg from `New`, `NewWithTimeout` and `NewWithClient` (@melekes)
   - [rpc/client/http] \#6176 Unexpose `WSEvents` (@melekes)
   - [rpc/jsonrpc/client/ws_client] \#6176 `NewWS` no longer accepts options (use `NewWSWithOptions` and `OnReconnect` funcs to configure the client) (@melekes)
-  - [rpc/jsonrpc/server] \#6204 Modify `WriteRPCResponseHTTP(Error)` to return an error (@melekes)
 
 - Blockchain Protocol
 
@@ -52,7 +51,6 @@ Friendly reminder: We have a [bug bounty program](https://hackerone.com/tendermi
 
 ### FEATURES
 
-- [rpc] \#6226 Index block events and expose a new RPC method, `/block_search`, to allow querying for blocks by `BeginBlock` and `EndBlock` events. (@alexanderbez)
 - [config] Add `--mode` flag and config variable. See [ADR-52](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-052-tendermint-mode.md) @dongsam
 
 ### IMPROVEMENTS
@@ -88,5 +86,3 @@ Friendly reminder: We have a [bug bounty program](https://hackerone.com/tendermi
 - [privval] \#5638 Increase read/write timeout to 5s and calculate ping interval based on it (@JoeKash)
 - [blockchain/v1] [\#5701](https://github.com/tendermint/tendermint/pull/5701) Handle peers without blocks (@melekes)
 - [blockchain/v1] \#5711 Fix deadlock (@melekes)
-- [rpc/jsonrpc/server] \#6191 Correctly unmarshal `RPCRequest` when data is `null` (@melekes)
-- [light/evidence] Adds logic to handle forward lunatic attacks (@cmwaters)