add new api to allow client control whether flutter boost handle the registration of all plugins

ios/Classes/Boost/FLBFlutterApplicationInterface.h

@@ -36,6 +36,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
                       withEngine:(FlutterEngine* _Nullable)engine
+                        withPluginRegisterred:(BOOL)registerPlugin
                          onStart:(void (^)(FlutterEngine *engine))callback;
 
 - (FlutterViewController *)flutterViewController;

ios/Classes/Boost/FlutterBoostPlugin.h

@@ -32,7 +32,7 @@ NS_ASSUME_NONNULL_BEGIN
 + (instancetype)sharedInstance;
 
 /**
- * 初始化FlutterBoost混合栈环境。应在程序使用混合栈之前调用。如在AppDelegate中
+ * 初始化FlutterBoost混合栈环境。应在程序使用混合栈之前调用。如在AppDelegate中。本函数默认需要flutter boost来注册所有插件。
  *
  * @param platform 平台层实现FLBPlatform的对象
  * @param callback 启动之后回调
@@ -40,7 +40,7 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
                          onStart:(void (^)(FlutterEngine *engine))callback;
 /**
- * 初始化FlutterBoost混合栈环境。应在程序使用混合栈之前调用。如在AppDelegate中
+ * 初始化FlutterBoost混合栈环境。应在程序使用混合栈之前调用。如在AppDelegate中。本函数默认需要flutter boost来注册所有插件。
  *
  * @param platform 平台层实现FLBPlatform的对象
  * @param engine   外部实例化engine后传入
@@ -50,6 +50,17 @@ NS_ASSUME_NONNULL_BEGIN
                           engine:(FlutterEngine* _Nullable)engine
                          onStart:(void (^)(FlutterEngine *engine))callback;
 
+/**
+ * 初始化FlutterBoost混合栈环境。应在程序使用混合栈之前调用。如在AppDelegate中。本函数可以控制是否需要flutter boost来注册所有插件
+ *
+ * @param platform 平台层实现FLBPlatform的对象
+ * @param engine   外部实例化engine后传入
+ * @param callback 启动之后回调
+ */
+- (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
+                          engine:(FlutterEngine* _Nullable)engine
+                          pluginRegisterred:(BOOL)registerPlugin
+                         onStart:(void (^)(FlutterEngine *engine))callback;
 #pragma mark - Some properties.
 - (BOOL)isRunning;
 

ios/Classes/Boost/FlutterBoostPlugin.m

@@ -114,13 +114,26 @@
 - (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
                          onStart:(void (^)(FlutterEngine *engine))callback;
 {
-    [self startFlutterWithPlatform:platform engine:nil onStart:callback];
+    [self startFlutterWithPlatform:platform
+                            engine:nil
+             pluginRegisterred:YES
+                           onStart:callback];
 }
 
 - (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
                          engine:(FlutterEngine* _Nullable)engine
                          onStart:(void (^)(FlutterEngine *engine))callback;
 {
+    [self startFlutterWithPlatform:platform
+                                 engine:engine
+                                  pluginRegisterred:YES
+                                   onStart:callback];
+}
+
+- (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
+                          engine:(FlutterEngine *)engine
+           pluginRegisterred:(BOOL)registerPlugin
+                         onStart:(void (^)(FlutterEngine * _Nonnull))callback{
     static dispatch_once_t onceToken;
     __weak __typeof__(self) weakSelf = self;
     dispatch_once(&onceToken, ^{
@@ -129,6 +142,7 @@
         self.application = [self->_factory createApplication:platform];
         [self.application startFlutterWithPlatform:platform
                                      withEngine:engine
+                                      withPluginRegisterred:registerPlugin
                                        onStart:callback];
     });
 }

ios/Classes/Engine/FLBFlutterApplication.m

@@ -51,6 +51,7 @@
 
 - (void)startFlutterWithPlatform:(id<FLBPlatform>)platform
                       withEngine:(FlutterEngine* _Nullable)engine
+                        withPluginRegisterred:(BOOL)registerPlugin
                          onStart:(void (^)(FlutterEngine *engine))callback
 {
     static dispatch_once_t onceToken;
@@ -58,6 +59,16 @@
         self.platform = platform;
         self.viewProvider = [[FLBFlutterEngine alloc] initWithPlatform:platform engine:engine];
         self.isRunning = YES;
+        if(registerPlugin){
+            Class clazz = NSClassFromString(@"GeneratedPluginRegistrant");
+            FlutterEngine *myengine = [self.viewProvider engine];
+            if (clazz && myengine) {
+                if ([clazz respondsToSelector:NSSelectorFromString(@"registerWithRegistry:")]) {
+                    [clazz performSelector:NSSelectorFromString(@"registerWithRegistry:")
+                                withObject:myengine];
+                }
+            }
+        }
         if(callback) callback(self.viewProvider.engine);
     });
 }

ios/Classes/Engine/FLBFlutterEngine.m

@@ -57,14 +57,6 @@
                                                           nibName:nil
                                                            bundle:nil];
         _dummy.name = kIgnoreMessageWithName;
-        
-        Class clazz = NSClassFromString(@"GeneratedPluginRegistrant");
-        if (clazz) {
-            if ([clazz respondsToSelector:NSSelectorFromString(@"registerWithRegistry:")]) {
-                [clazz performSelector:NSSelectorFromString(@"registerWithRegistry:")
-                            withObject:_engine];
-            }
-        }
     }
     
     return self;