Auto merge of #27438 - paulrouget:crashReporter, r=jdm

UWP Crash reporter

This is supposed to address #27167 and #26523. Also fix #27435.

These changes are still WIP as I found a few bugs, it needs more testing and the actual code to upload is not implemented yet. But I'd like to get an early feedback.

First, panics are caught via `panic::set_hook` instead of `catch_unwind` allowing us to catch more panics.
We also now report panics reported via the `Embedder:Panic` message.
Once the panic is caught, if possible, we try to recover.
I haven't found a way to recover when the panic is caught is a non-GL thread. We need a generic way to throw from the UWP code, and even trying to add a UnhandledEvent handler doesn't appear to work.

Once a panic is caught (even if we can not recover) a crash-report file is created, including the backtrace, stdout, and the current url.

If the app did not crash at that point, or after a restart if it did, we check if the crash report file is present, and if so, we present a panel to the user to allow them to upload the report. At that point the user can also add details to the report.

<img width="1079" alt="Screen Shot 2020-07-29 at 12 35 44" src="https://user-images.githubusercontent.com/373579/88790406-6d777180-d198-11ea-9237-6f80dc9d0340.png">

components/config/prefs.rs

@@ -482,6 +482,9 @@ mod gen {
                 max_length: i64,
             },
             shell: {
+                crash_reporter: {
+                    enabled: bool,
+                },
                 homepage: String,
                 keep_screen_on: {
                     enabled: bool,