[Shell] Update stale comments after multi-view (#39298)

runtime/platform_data.h

diff --git a/runtime/platform_data.h b/runtime/platform_data.h
index ca7b683..8b11b34 100644
--- a/runtime/platform_data.h
+++ b/runtime/platform_data.h
@@ -14,17 +14,18 @@
 namespace flutter {
 
 //------------------------------------------------------------------------------
-/// The struct of platform-specific data used for initializing ui.Window.
+/// The struct of platform-specific data used for initializing
+/// ui.PlatformDispatcher.
 ///
-/// framework may request data from ui.Window before platform is properly
-/// configured. Engine this struct to set the desired default value for
-/// ui.Window when creating Shell before platform is ready to send the real
+/// The framework may request data from ui.PlatformDispatcher before the
+/// platform is properly configured. When creating the Shell, the engine sets
+/// this struct to default values until the platform is ready to send the real
 /// data.
 ///
 /// See also:
 ///
 ///  * flutter::Shell::Create, which takes a platform_data to initialize the
-///    ui.Window attached to it.
+///    ui.PlatformDispatcher attached to it.
 struct PlatformData {
   PlatformData();
 

shell/common/shell.h

diff --git a/shell/common/shell.h b/shell/common/shell.h
index f51edc9..2ecf71d 100644
--- a/shell/common/shell.h
+++ b/shell/common/shell.h
@@ -452,7 +452,7 @@
   std::atomic<bool> needs_report_timings_{false};
 
   // Whether there's a task scheduled to report the timings to Dart through
-  // ui.Window.onReportTimings.
+  // ui.PlatformDispatcher.onReportTimings.
   bool frame_timings_report_scheduled_ = false;
 
   // Vector of FrameTiming::kCount * n timestamps for n frames whose timings