Fix errors with component stacks reported as warnings

Summary:
Ok so this is a doozy.

## Overview
There was a report that some console.error calls were being shown as warnings in LogBox but as console.error in the console. The only time we should downlevel an error to a warning is if the custom warning filter says so (which is used for some noisy legacy warning filter warnings internally).

However, in when I switched from using the `Warning: ` prefix, to using the presence of component stacks, I subtly missed the default warning filter case.

In the internal warning filter, the `monitorEvent` is always set to something other than `unknown` and if it's set to `warning_unhandled` then `suppressDialog_LEGACY` is always false.

However, the default values for the warning filter are that `monitorEvent = 'unknown'` and `suppressDialog_LEGACY = true`. In this case, we would downlevel the error to a warning.

## What's the fix?
Change the default settings for the warning filter.

## What's the root cause?

Bad configuration combinations in a fragile system that needs cleaned up, and really really bad testing practices with excessive mocking and snapshot testing (I can say that, I wrote the tests)

## How could it have been caught?
It was, but I turned off the integration tests while landing the component stack changes because of mismatches between flags internally and in OSS, and never turned them back on.

Changelog: [General] [Fixed] - Fix logbox reporting React errors as Warnings

Differential Revision: D63349613

packages/react-native/Libraries/LogBox/Data/LogBoxData.js

@@ -82,9 +82,9 @@ let warningFilter: WarningFilter = function (format) {
   return {
     finalFormat: format,
     forceDialogImmediately: false,
-    suppressDialog_LEGACY: true,
+    suppressDialog_LEGACY: false,
     suppressCompletely: false,
-    monitorEvent: 'unknown',
+    monitorEvent: 'warning_unhandled',
     monitorListVersion: 0,
     monitorSampleRate: 1,
   };

packages/react-native/Libraries/LogBox/__tests__/LogBox-test.js

@@ -506,6 +506,45 @@ describe('LogBox', () => {
       'Custom: after installing for the second time',
     );
   });
+
+  it('registers errors with component stack as errors by default, when ExceptionManager is registered first', () => {
+    jest.spyOn(LogBoxData, 'checkWarningFilter');
+    jest.spyOn(LogBoxData, 'addLog');
+
+    ExceptionsManager.installConsoleErrorReporter();
+    LogBox.install();
+
+    console.error(
+      'HIT\n    at Text (/path/to/Component:30:175)\n    at DoesNotUseKey',
+    );
+
+    expect(LogBoxData.addLog).toBeCalledWith(
+      expect.objectContaining({level: 'error'}),
+    );
+    expect(LogBoxData.checkWarningFilter).toBeCalledWith(
+      'HIT\n    at Text (/path/to/Component:30:175)\n    at DoesNotUseKey',
+    );
+  });
+
+  it('registers errors with component stack as errors by default, when ExceptionManager is registered second', () => {
+    jest.spyOn(LogBoxData, 'checkWarningFilter');
+    jest.spyOn(LogBoxData, 'addLog');
+
+    LogBox.install();
+    ExceptionsManager.installConsoleErrorReporter();
+
+    console.error(
+      'HIT\n    at Text (/path/to/Component:30:175)\n    at DoesNotUseKey',
+    );
+
+    expect(LogBoxData.addLog).toBeCalledWith(
+      expect.objectContaining({level: 'error'}),
+    );
+    expect(LogBoxData.checkWarningFilter).toBeCalledWith(
+      'HIT\n    at Text (/path/to/Component:30:175)\n    at DoesNotUseKey',
+    );
+  });
+
   it('registers errors without component stack as errors by default, when ExceptionManager is registered first', () => {
     jest.spyOn(LogBoxData, 'checkWarningFilter');
     jest.spyOn(LogBoxData, 'addException');

packages/react-native/Libraries/LogBox/__tests__/__snapshots__/LogBox-integration-test.js.snap

@@ -19,7 +19,7 @@ Array [
     "extraData": Object {
       "redacted": true,
     },
-    "level": "warn",
+    "level": "error",
     "message": Object {
       "content": "Warning: Manual console error",
       "substitutions": Array [],
@@ -91,7 +91,7 @@ Array [
       },
     ],
     "componentStackType": "stack",
-    "level": "warn",
+    "level": "error",
     "message": Object {
       "content": "Warning: Invalid prop \`invalid\` supplied to \`React.Fragment\`. React.Fragment can only have \`key\` and \`children\` props.",
       "substitutions": Array [
@@ -146,7 +146,7 @@ Array [
       },
     ],
     "componentStackType": "stack",
-    "level": "warn",
+    "level": "error",
     "message": Object {
       "content": "Warning: Each child in a list should have a unique \\"key\\" prop.