fix(apm|tracing): Make sure Performance Observer takeRecords() is defined (#2825)

* fix(apm|tracing): Make sure Performance Observer takeRecords() is defined

In Safari 14.0 and below, `PerformanceObserver.takeRecords()` is not defined. We should defend against it by
checking for existence before usage. In the future, we may have to look for another way to track PO records
for these browsers. Also occurs in IE 11.

Author: AbhiPrasad

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 - "You miss 100 percent of the chances you don't take. — Wayne Gretzky" — Michael Scott
+- [apm/tracing] fix: Make sure Performance Observer takeRecords() is defined
 
 ## 5.21.1
 

packages/apm/src/integrations/tracing.ts

@@ -760,7 +760,9 @@ export class Tracing implements Integration {
       });
 
       Tracing._forceLCP = (): void => {
-        po.takeRecords().forEach(updateLCP);
+        if (po.takeRecords) {
+          po.takeRecords().forEach(updateLCP);
+        }
       };
     } catch (e) {
       // Do nothing if the browser doesn't support this API.

packages/tracing/src/browser/metrics.ts

@@ -170,7 +170,9 @@ export class MetricsInstrumentation {
       });
 
       this._forceLCP = () => {
-        po.takeRecords().forEach(updateLCP);
+        if (po.takeRecords) {
+          po.takeRecords().forEach(updateLCP);
+        }
       };
     } catch (e) {
       // Do nothing if the browser doesn't support this API.