Fix randomic NPE when pressing menus during operations

Author: facchinm

arduino-core/src/cc/arduino/packages/Uploader.java

@@ -134,7 +134,11 @@ protected boolean executeUploadCommand(String command[]) throws Exception {
       if (!process.waitFor(2, TimeUnit.MINUTES)) {
         process.destroyForcibly();
       }
-      result = process.exitValue();
+      if (!process.isAlive()) {
+        result = process.exitValue();
+      } else {
+        result = 0;
+      }
     } catch (Exception e) {
       e.printStackTrace();
     }

arduino-core/src/processing/app/Platform.java

@@ -181,7 +181,7 @@ public  List<String> listSerialsNames(){
     return list;
   }
 
-  public Map<String, Object> resolveDeviceByVendorIdProductId(String serial, Map<String, TargetPackage> packages) {
+  public synchronized Map<String, Object> resolveDeviceByVendorIdProductId(String serial, Map<String, TargetPackage> packages) {
     String vid_pid_iSerial = resolveDeviceAttachedToNative(serial);
     for (TargetPackage targetPackage : packages.values()) {
       for (TargetPlatform targetPlatform : targetPackage.getPlatforms().values()) {