[No QA][TS migration] Migrate 'Metrics' lib to TypeScript

src/libs/Metrics/index.native.ts

@@ -0,0 +1,14 @@
+import CONFIG from '../../CONFIG';
+import {CanCaptureOnyxMetrics, CanCapturePerformanceMetrics} from './types';
+
+/**
+ * Is capturing performance stats enabled.
+ */
+const canCapturePerformanceMetrics: CanCapturePerformanceMetrics = () => CONFIG.CAPTURE_METRICS;
+
+/**
+ * Is capturing Onyx stats enabled.
+ */
+const canCaptureOnyxMetrics: CanCaptureOnyxMetrics = () => CONFIG.ONYX_METRICS;
+
+export {canCapturePerformanceMetrics, canCaptureOnyxMetrics};

src/libs/Metrics/index.ts

@@ -0,0 +1,9 @@
+import CONFIG from '../../CONFIG';
+import {CanCaptureOnyxMetrics, CanCapturePerformanceMetrics} from './types';
+
+// We don't capture performance metrics on web as there are enough tools available
+const canCapturePerformanceMetrics: CanCapturePerformanceMetrics = () => false;
+
+const canCaptureOnyxMetrics: CanCaptureOnyxMetrics = () => CONFIG.ONYX_METRICS;
+
+export {canCapturePerformanceMetrics, canCaptureOnyxMetrics};

src/libs/Metrics/types.ts

@@ -0,0 +1,4 @@
+type CanCapturePerformanceMetrics = () => boolean;
+type CanCaptureOnyxMetrics = () => boolean;
+
+export type {CanCapturePerformanceMetrics, CanCaptureOnyxMetrics};