Add AssertLockHeld for cs_main to ChainActive-using functions

All functions that use ChainActive but do not aquire the cs_main
lock themselves, need to be called with the cs_main lock held.

This commit adds assertions to all externally callable functions
that use chainActive or chainMostWork.

This will flag usages when built with -DDEBUG_LOCKORDER.

src/qt/transactionrecord.cpp

@@ -150,6 +150,7 @@ QList<TransactionRecord> TransactionRecord::decomposeTransaction(const CWallet *
 
 void TransactionRecord::updateStatus(const CWalletTx &wtx)
 {
+    AssertLockHeld(cs_main);
     // Determine transaction status
 
     // Find the block the tx is in
@@ -234,6 +235,7 @@ void TransactionRecord::updateStatus(const CWalletTx &wtx)
 
 bool TransactionRecord::statusUpdateNeeded()
 {
+    AssertLockHeld(cs_main);
     return status.cur_num_blocks != chainActive.Height();
 }