MetricKit SDK incorporation (#8436)

Adds MetricKit diagnostic report collection (for allowlisted apps only).

Author: elenadoty

Crashlytics/CHANGELOG.md

@@ -1,3 +1,6 @@
+# Unreleased
+- [added] Internal SDK updates to test potential future MetricKit support.
+
 # v8.4.0
 - [fixed] Bump Promises dependency. (#8365)
 

Crashlytics/Crashlytics/Controllers/FIRCLSMetricKitManager.h

@@ -0,0 +1,52 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <Availability.h>
+#import <Foundation/Foundation.h>
+
+#if defined(__IPHONE_15_0)
+#define CLS_METRICKIT_SUPPORTED (__has_include(<MetricKit/MetricKit.h>) && TARGET_OS_IOS)
+#else
+#define CLS_METRICKIT_SUPPORTED 0
+#endif
+
+#if CLS_METRICKIT_SUPPORTED
+#import <MetricKit/MetricKit.h>
+
+#import "Crashlytics/Crashlytics/Controllers/FIRCLSExistingReportManager.h"
+#import "Crashlytics/Crashlytics/Models/FIRCLSFileManager.h"
+
+#if __has_include(<FBLPromises/FBLPromises.h>)
+#import <FBLPromises/FBLPromises.h>
+#else
+#import "FBLPromises.h"
+#endif
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface FIRCLSMetricKitManager : NSObject <MXMetricManagerSubscriber>
+
+- (instancetype)initWithManagerData:(FIRCLSManagerData *)managerData
+              existingReportManager:(FIRCLSExistingReportManager *)existingReportManager
+                        fileManager:(FIRCLSFileManager *)fileManager;
+
+- (instancetype)init NS_UNAVAILABLE;
+- (void)registerMetricKitManager;
+- (FBLPromise *)waitForMetricKitDataAvailable;
+- (void)processDiagnosticPayloads:(NSArray<MXDiagnosticPayload *> *)payloads;
+
+@end
+
+NS_ASSUME_NONNULL_END
+#endif  // CLS_METRICKIT_SUPPORTED