[CQ] [unchecked cast]: fix generic bounds (#8087)

Fix up the generic wildcard bounds so we can remove these unsafe casts
(that are spamming the logs).

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Author: pq

flutter-idea/src/io/flutter/FlutterErrorReportSubmitter.java

@@ -56,8 +56,7 @@ public boolean submit(@NotNull IdeaLoggingEvent[] events,
                         @NotNull Component parentComponent,
                         @NotNull Consumer<? super SubmittedReportInfo> consumer) {
     if (events.length == 0) {
-      // Don't remove the cast until a later version of Android Studio.
-      fail(((Consumer<SubmittedReportInfo>)consumer));
+      fail(consumer);
       return false;
     }
 
@@ -97,8 +96,7 @@ public boolean submit(@NotNull IdeaLoggingEvent[] events,
     final DataContext dataContext = DataManager.getInstance().getDataContext(parentComponent);
     final Project project = PROJECT.getData(dataContext);
     if (project == null) {
-      // Don't remove the cast until a later version of Android Studio.
-      fail(((Consumer<SubmittedReportInfo>)consumer));
+      fail(consumer);
       return false;
     }
 
@@ -187,8 +185,7 @@ public boolean submit(@NotNull IdeaLoggingEvent[] events,
     final VirtualFile file = scratchRoot.createScratchFile(project, "bug-report.md", PlainTextLanguage.INSTANCE, text);
 
     if (file == null) {
-      // Don't remove the cast until a later version of Android Studio.
-      fail(((Consumer<SubmittedReportInfo>)consumer));
+      fail(consumer);
       return false;
     }
 
@@ -218,7 +215,7 @@ private static String getFlutterVersion(final FlutterSdk sdk) {
     }
   }
 
-  private static void fail(@NotNull Consumer<SubmittedReportInfo> consumer) {
+  private static void fail(@NotNull Consumer<? super SubmittedReportInfo> consumer) {
     consumer.consume(new SubmittedReportInfo(
       null,
       null,