### Describe the issue

Restarting bitcoin, mempool starts filling from scratch.

### Can you reliably reproduce the issue?
#### If so, please list the steps to reproduce below:
1. Wait for mempool to reach for example 3000 transactions
2. Restart bitcoin
3. Watch mempool filling slowly from scratch

### Expected behaviour
Mempool would already contain ~3000 TX on startup

### Actual behaviour
It starts at 0 and fills up slowly with a few per second.

### Screenshots.
http://imgur.com/a/or82d

### What version of bitcoin-core are you using?
Windows x64 0.14rc1 binary from https://bitcoin.org/bin/bitcoin-core-0.14.0/test.rc1/


### Any extra information that might be useful in the debugging process.
I may not be aware of how the mempool.dat thing works and there could just be a misunderstanding.

PrecomputedTransactionData txdata(tx);
        if (!CheckInputs(tx, state, view, true, scriptVerifyFlags, true, txdata)) {
            
            
            
            CValidationState stateDummy; 
            if (!tx.HasWitness() && CheckInputs(tx, stateDummy, view, true, scriptVerifyFlags & ~(SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_CLEANSTACK), true, txdata) &&
                !CheckInputs(tx, stateDummy, view, true, scriptVerifyFlags & ~SCRIPT_VERIFY_CLEANSTACK, true, txdata)) {
                
                state.SetCorruptionPossible();
            }
            return false; 
        }
        
        
        
        
        
        
        
        
        
        if (!CheckInputs(tx, state, view, true, MANDATORY_SCRIPT_VERIFY_FLAGS, true, txdata))
        {
            return error("%s: BUG! PLEASE REPORT THIS! ConnectInputs failed against MANDATORY but not STANDARD flags %s, %s",
                __func__, hash.ToString(), FormatStateMessage(state));
        }
        
        BOOST_FOREACH(const CTxMemPool::txiter it, allConflicting)