Enable storing last-dispatched exception per-thread.

components/browser_watcher/postmortem_report_collector_unittest.cc

Index: components/browser_watcher/postmortem_report_collector_unittest.cc
diff --git a/components/browser_watcher/postmortem_report_collector_unittest.cc b/components/browser_watcher/postmortem_report_collector_unittest.cc
index 72a434c97f3cfcee133bf9392e2048e912ac46e3..12dd88d14e594edb4a9b6ca7b4b28543609f65b8 100644
--- a/components/browser_watcher/postmortem_report_collector_unittest.cc
+++ b/components/browser_watcher/postmortem_report_collector_unittest.cc
@@ -341,7 +341,7 @@ TEST(PostmortemReportCollectorTest, CollectRandomFile) {
 namespace {
 
 // Parameters for the activity tracking.
-const size_t kFileSize = 2 * 1024;
+const size_t kFileSize = 64 << 10;  // 64 KiB
 const int kStackDepth = 6;
 const uint64_t kAllocatorId = 0;
 const char kAllocatorName[] = "PostmortemReportCollectorCollectionTest";