Inline the _findDefaultThread function inside getDefaultSelectedThreadIndexes

Author: canova

src/profile-logic/tracks.js

@@ -795,15 +795,27 @@ function getDefaultSelectedThreadIndexes(
       })
     );
   }
-  const defaultThread = _findDefaultThread(
+
+  const { threads } = profile;
+  if (threads.length === 0) {
+    throw new Error('Expected to find a thread index to select.');
+  }
+
+  const threadOrder = defaultThreadOrder(
     visibleThreadIndexes,
-    profile.threads,
+    threads,
     threadActivityScores
   );
-  const defaultThreadIndex = profile.threads.indexOf(defaultThread);
-  if (defaultThreadIndex === -1) {
-    throw new Error('Expected to find a thread index to select.');
-  }
+
+  // Try to find a tab process with the highest activity score. If it can't
+  // find one, select the first thread with the highest one.
+  const defaultThreadIndex =
+    threadOrder.find(
+      (threadIndex) =>
+        threads[threadIndex].name === 'GeckoMain' &&
+        threads[threadIndex].processType === 'tab'
+    ) ?? threadOrder[0];
+
   return new Set([defaultThreadIndex]);
 }
 
@@ -1320,34 +1332,6 @@ function _computeThreadSampleScore(
   return nonIdleSampleCount * referenceCPUDeltaPerInterval;
 }
 
-function _findDefaultThread(
-  visibleThreadIndexes: ThreadIndex[],
-  threads: RawThread[],
-  threadActivityScores: Array<ThreadActivityScore>
-): RawThread | null {
-  if (threads.length === 0) {
-    // Tests may have no threads.
-    return null;
-  }
-
-  const threadOrder = defaultThreadOrder(
-    visibleThreadIndexes,
-    threads,
-    threadActivityScores
-  );
-
-  // Try to find a tab process with the highest activity score. If it can't
-  // find one, select the first thread with the highest one.
-  const defaultThreadIndex =
-    threadOrder.find(
-      (threadIndex) =>
-        threads[threadIndex].name === 'GeckoMain' &&
-        threads[threadIndex].processType === 'tab'
-    ) ?? threadOrder[0];
-
-  return threads[defaultThreadIndex];
-}
-
 function _indexesAreValid(listLength: number, indexes: number[]) {
   return (
     // The item length is valid.