Add cancel methods to the AsyncTaskHandle.

Still not sure about this duplication of cancel methods, but lets see how it goes.

zanata-war/src/main/java/org/zanata/action/CopyTransManager.java

@@ -153,7 +153,7 @@ public void cancelCopyTrans( HProjectIteration iteration )
       {
          CopyTransProcessKey key = CopyTransProcessKey.getKey(iteration);
          CopyTransTaskHandle handle = this.getCopyTransProcessHandle(iteration);
-         handle.cancel(true);
+         handle.forceCancel();
          handle.setCancelledTime(System.currentTimeMillis());
          handle.setCancelledBy(identity.getCredentials().getUsername());
       }

zanata-war/src/main/java/org/zanata/action/ProcessManagerAction.java

@@ -81,7 +81,7 @@ public void clearAllFinished()
 
    public void cancel( AsyncTaskHandle handle )
    {
-      handle.cancel(false);
+      handle.cancel();
    }
 
 }

zanata-war/src/main/java/org/zanata/action/ProjectIterationZipFileAction.java

@@ -47,7 +47,7 @@ public void prepareIterationZipFile(boolean offlinePo)
       if( this.zipFilePrepHandle != null && !this.zipFilePrepHandle.isDone() )
       {
          // Cancel any other processes for this conversation
-         this.zipFilePrepHandle.cancel(true);
+         this.zipFilePrepHandle.forceCancel();
       }
 
       // Start a zip file task
@@ -61,7 +61,7 @@ public void prepareIterationZipFile(boolean offlinePo)
    @End
    public void cancelFileDownload()
    {
-      this.zipFilePrepHandle.cancel(false);
+      this.zipFilePrepHandle.cancel();
    }
 
    public Object getProjectIteration()

zanata-war/src/main/java/org/zanata/action/ReindexActionBean.java

@@ -175,7 +175,7 @@ public void reindexDatabase()
 
    public void cancel()
    {
-      reindexAsync.getProcessHandle().cancel(false);
+      reindexAsync.getProcessHandle().cancel();
    }
 
    public boolean isCanceled()

zanata-war/src/main/java/org/zanata/async/AsyncTaskHandle.java

@@ -61,4 +61,30 @@ public int increaseProgress(int increaseBy)
       currentProgress += increaseBy;
       return currentProgress;
    }
+
+   /**
+    * Cancels the task without trying to forcefully interrupt the task.
+    * This is equivalent to calling <code>cancel(false)</code>
+    *
+    * @see AsyncTaskHandle#cancel(boolean)
+    * @return false if the task could not be cancelled, typically because it has already completed normally;
+    * true otherwise
+    */
+   public boolean cancel()
+   {
+      return cancel(false);
+   }
+
+   /**
+    * Cancels the task, forcefully cancelling the task if needed.
+    * This is equivalent to calling <code>cancel(true)</code>
+    *
+    * @see AsyncTaskHandle#cancel(boolean)
+    * @return false if the task could not be cancelled, typically because it has already completed normally;
+    * true otherwise
+    */
+   public boolean forceCancel()
+   {
+      return cancel(true);
+   }
 }

zanata-war/src/main/java/org/zanata/webtrans/server/rpc/DownloadAllFilesHandler.java

@@ -72,7 +72,7 @@ public DownloadAllFilesResult execute(DownloadAllFilesAction action, ExecutionCo
          if (this.zipFilePrepHandle != null && !this.zipFilePrepHandle.isDone())
          {
             // Cancel any other processes
-            this.zipFilePrepHandle.cancel(false);
+            this.zipFilePrepHandle.cancel();
          }
 
          // Build a new task