RNCamera添加rectOfInterest属性，review by redding

@@ -109,7 +109,13 @@ export default class Camera extends Component {
     type: PropTypes.oneOfType([
       PropTypes.string,
       PropTypes.number
-    ])
+    ]),
+    rectOfCameraInterest: PropTypes.shape({
+        x: React.PropTypes.number,
+        y: React.PropTypes.number,
+        width: React.PropTypes.number,
+        height: React.PropTypes.number
+    }),
   };
 
   static defaultProps = {

@@ -72,6 +72,7 @@ typedef NS_ENUM(NSInteger, RCTCameraTorchMode) {
 @property (nonatomic, strong) RCTPromiseResolveBlock videoResolve;
 @property (nonatomic, strong) RCTPromiseRejectBlock videoReject;
 @property (nonatomic, strong) RCTCamera *camera;
+@property (nonatomic, assign) CGRect rectOfCameraInterest;
 
 
 - (void)changeOrientation:(NSInteger)orientation;

@@ -271,6 +271,10 @@ RCT_CUSTOM_VIEW_PROPERTY(captureAudio, BOOL, RCTCamera) {
   }
 }
 
+RCT_CUSTOM_VIEW_PROPERTY(rectOfCameraInterest, CGRect, RCTCamera) {
+  self.rectOfCameraInterest = [RCTConvert CGRect:json];
+}
+
 - (NSArray *)customDirectEventTypes
 {
     return @[
@@ -416,6 +420,7 @@ RCT_EXPORT_METHOD(hasFlash:(RCTPromiseResolveBlock)resolve reject:(RCTPromiseRej
       [metadataOutput setMetadataObjectsDelegate:self queue:self.sessionQueue];
       [self.session addOutput:metadataOutput];
       [metadataOutput setMetadataObjectTypes:self.barCodeTypes];
+      metadataOutput.rectOfInterest = self.rectOfCameraInterest;
       self.metadataOutput = metadataOutput;
     }