[NC-1384] synchronised fixes

ethereum/blockcreation/src/main/java/tech/pegasys/pantheon/ethereum/blockcreation/AbstractMiningCoordinator.java

@@ -91,18 +91,20 @@ public void onBlockAdded(final BlockAddedEvent event, final Blockchain blockchai
     synchronized (this) {
       if (isEnabled && shouldStartNewMiner(event)) {
         haltCurrentMiningOperation();
-        if (syncState.getInSync()) {
+        if (syncState.isInSync()) {
           startAsyncMiningOperation();
         }
       }
     }
   }
 
   public void inSyncChanged(final boolean inSync) {
-    if (isEnabled && inSync) {
-      startAsyncMiningOperation();
-    } else if (!inSync) {
-      haltCurrentMiningOperation();
+    synchronized (this) {
+      if (isEnabled && inSync) {
+        startAsyncMiningOperation();
+      } else if (!inSync) {
+        haltCurrentMiningOperation();
+      }
     }
   }
 

ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/manager/ChainState.java

@@ -22,11 +22,6 @@
 import com.google.common.base.MoreObjects;
 
 public class ChainState {
-
-  public interface EstimatedHeightObserver {
-    void estimatedHeightChanged(long newHeight);
-  }
-
   // The best block by total difficulty that we know about
   private final BestBlock bestBlock = new BestBlock();
   // The highest block that we've seen

ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/state/SyncState.java

@@ -87,15 +87,15 @@ public SyncTarget setSyncTarget(final EthPeer peer, final BlockHeader commonAnce
   }
 
   private void checkInSync() {
-    final boolean newInSync = getInSync();
+    final boolean newInSync = isInSync();
 
     if (newInSync != lastInSync) {
       lastInSync = newInSync;
       inSyncSubscribers.forEach(c -> c.accept(newInSync));
     }
   }
 
-  public boolean getInSync() {
+  public boolean isInSync() {
     return syncTarget
         .map(t -> t.estimatedTargetHeight() <= blockchain.getChainHeadBlockNumber())
         .orElse(false);