[CQ] remove stale installation failure analytics (#8234)

As per a conversation w/ @helin24, the `eventName` string is likely an
artifact from when JXBrowser was being evaluated but is unused now. We
agreed to remove it and add back when analytics are in place (and is
deemed useful).


![image](https://github.com/user-attachments/assets/4b45f73a-fc75-413f-9025-045cc571a3c8)



I also snuck in some null-awareness. There's an assert that ensures
`fileName` entries are not null allowing us to update some method
signatures making a few asserts redundant.


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portions to this PR.

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Author: pq

flutter-idea/src/io/flutter/jxbrowser/JxBrowserManager.java

@@ -169,14 +169,6 @@ private void setStatusFailed(@NotNull InstallationFailedReason reason) {
   }
 
   private void setStatusFailed(@NotNull InstallationFailedReason reason, @Nullable Long time) {
-    final StringBuilder eventName = new StringBuilder();
-    eventName.append("installationFailed-");
-    eventName.append(reason.failureType);
-    if (reason.detail != null) {
-      eventName.append("-");
-      eventName.append(reason.detail);
-    }
-
     latestFailureReason = reason;
     status.set(JxBrowserStatus.INSTALLATION_FAILED);
     installation.complete(JxBrowserStatus.INSTALLATION_FAILED);
@@ -275,14 +267,13 @@ public void setUp(@NotNull String projectName) {
     downloadJxBrowser(fileNames);
   }
 
-  protected void downloadJxBrowser(@NotNull String[] fileNames) {
+  protected void downloadJxBrowser(@NotNull String @NotNull [] fileNames) {
     // The FileDownloader API is used by other plugins - e.g.
     // https://github.com/JetBrains/intellij-community/blob/b09f8151e0d189d70363266c3bb6edb5f6bfeca4/plugins/markdown/src/org/intellij/plugins/markdown/ui/preview/javafx/JavaFXInstallator.java#L48
     final List<FileDownloader> fileDownloaders = new ArrayList<>();
     final DownloadableFileService service = DownloadableFileService.getInstance();
     assert service != null;
     for (String fileName : fileNames) {
-      assert fileName != null;
       final DownloadableFileDescription
         description = service.createFileDescription(jxBrowserUtils.getDistributionLink(fileName), fileName);
       fileDownloaders.add(service.createDownloader(Collections.singletonList(description), fileName));
@@ -340,14 +331,13 @@ public void run(@NotNull ProgressIndicator indicator) {
     }
   }
 
-  private void loadClasses(@NotNull String[] fileNames) {
+  private void loadClasses(@NotNull String @NotNull [] fileNames) {
     final List<Path> paths = new ArrayList<>();
     final ClassLoader current = Thread.currentThread().getContextClassLoader();
     try {
       Thread.currentThread().setContextClassLoader(this.getClass().getClassLoader());
       try {
         for (String fileName : fileNames) {
-          assert fileName != null;
           paths.add(Paths.get(getFilePath(fileName)));
         }
         //noinspection ConstantConditions