fixed build files

lib/ui/BUILD.gn

@@ -154,6 +154,7 @@ source_set("ui") {
     "//flutter/impeller/runtime_stage",
     "//flutter/runtime:dart_plugin_registrant",
     "//flutter/runtime:test_font",
+    "//flutter/shell/common:platform_message_handler",
     "//flutter/third_party/tonic",
     "//third_party/dart/runtime/bin:dart_io_api",
     "//third_party/rapidjson",

shell/common/BUILD.gn

@@ -59,6 +59,12 @@ template("dart_embedder_resources") {
   }
 }
 
+source_set("platform_message_handler") {
+  sources = [ "platform_message_handler.h" ]
+  public_configs = [ "//flutter:config" ]
+  deps = [ "//flutter/fml:fml" ]
+}
+
 source_set("common") {
   sources = [
     "animator.cc",
@@ -75,7 +81,6 @@ source_set("common") {
     "engine.h",
     "pipeline.cc",
     "pipeline.h",
-    "platform_message_handler.h",
     "platform_view.cc",
     "platform_view.h",
     "pointer_data_dispatcher.cc",
@@ -115,6 +120,7 @@ source_set("common") {
   public_configs = [ "//flutter:config" ]
 
   public_deps = [
+    ":platform_message_handler",
     "//flutter/shell/version",
     "//flutter/third_party/tonic",
     "//flutter/third_party/txt",

shell/common/platform_message_handler.h

@@ -7,10 +7,12 @@
 
 #include <memory>
 
-#include "flutter/lib/ui/window/platform_message.h"
+#include "flutter/fml/mapping.h"
 
 namespace flutter {
 
+class PlatformMessage;
+
 /// An interface over the ability to handle PlatformMessages that are being sent
 /// from Flutter to the host platform.
 class PlatformMessageHandler {

shell/platform/darwin/ios/platform_message_handler_ios.mm

@@ -5,6 +5,7 @@
 #import "flutter/shell/platform/darwin/ios/platform_message_handler_ios.h"
 
 #import "flutter/fml/trace_event.h"
+#import "flutter/lib/ui/window/platform_message.h"
 #import "flutter/shell/platform/darwin/common/buffer_conversions.h"
 #import "flutter/shell/platform/darwin/common/framework/Headers/FlutterBinaryMessenger.h"