Removed main.h dependency from rpcserver.cpp

Rebased by @laanwj:

- update for RPC methods added since 84d13ee: setmocktime,
  invalidateblock, reconsiderblock. Only the first, setmocktime, required a change,
  the other two are thread safe.

src/rpcmisc.cpp

@@ -69,6 +69,12 @@ Value getinfo(const Array& params, bool fHelp)
             + HelpExampleRpc("getinfo", "")
         );
 
+#ifdef ENABLE_WALLET
+    LOCK2(cs_main, pwalletMain ? &pwalletMain->cs_wallet : NULL);
+#else
+    LOCK(cs_main);
+#endif
+
     proxyType proxy;
     GetProxy(NET_IPV4, proxy);
 
@@ -172,6 +178,12 @@ Value validateaddress(const Array& params, bool fHelp)
             + HelpExampleRpc("validateaddress", "\"1PSSGeFHDnKNxiEyFrD1wcEaHr9hrQDDWc\"")
         );
 
+#ifdef ENABLE_WALLET
+    LOCK2(cs_main, pwalletMain ? &pwalletMain->cs_wallet : NULL);
+#else
+    LOCK(cs_main);
+#endif
+
     CBitcoinAddress address(params[0].get_str());
     bool isValid = address.IsValid();
 
@@ -329,6 +341,8 @@ Value verifymessage(const Array& params, bool fHelp)
             + HelpExampleRpc("verifymessage", "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XZ\", \"signature\", \"my message\"")
         );
 
+    LOCK(cs_main);
+
     string strAddress  = params[0].get_str();
     string strSign     = params[1].get_str();
     string strMessage  = params[2].get_str();
@@ -372,6 +386,8 @@ Value setmocktime(const Array& params, bool fHelp)
     if (!Params().MineBlocksOnDemand())
         throw runtime_error("setmocktime for regression testing (-regtest mode) only");
 
+    LOCK(cs_main);
+
     RPCTypeCheck(params, boost::assign::list_of(int_type));
     SetMockTime(params[0].get_int64());