Reduce flakiness in EndToEnd probing tests.

webrtc/video/end_to_end_tests.cc

Index: webrtc/video/end_to_end_tests.cc
diff --git a/webrtc/video/end_to_end_tests.cc b/webrtc/video/end_to_end_tests.cc
index 6f030c3b58ff6cc136f6b3ed10c9398a73ac155d..174dc5fd2db8591c82ba7a7c0026d07ec35dfe8e 100644
--- a/webrtc/video/end_to_end_tests.cc
+++ b/webrtc/video/end_to_end_tests.cc
@@ -2236,43 +2236,54 @@ class ProbingTest : public test::EndToEndTest {
 TEST_F(EndToEndTest, MAYBE_InitialProbing) {
   class InitialProbingTest : public ProbingTest {
    public:
-    InitialProbingTest() : ProbingTest(300000) {}
+    explicit InitialProbingTest(bool* success)
+        : ProbingTest(300000), success_(success) {}
 
     void PerformTest() override {
       int64_t start_time_ms = clock_->TimeInMilliseconds();
       do {
-        if (clock_->TimeInMilliseconds() - start_time_ms > kTimeoutMs) {
-          ADD_FAILURE() << "Timed out while waiting for initial probing.";
+        if (clock_->TimeInMilliseconds() - start_time_ms > kTimeoutMs)
           break;
-        }
 
         Call::Stats stats = sender_call_->GetStats();
         // Initial probing is done with a x3 and x6 multiplier of the start
         // bitrate, so a x4 multiplier is a high enough threshold.
-        if (stats.send_bandwidth_bps > 4 * 300000)
+        if (stats.send_bandwidth_bps > 4 * 300000) {
+          *success_ = true;
           break;
+        }
       } while (!observation_complete_.Wait(20));
     }
 
    private:
     const int kTimeoutMs = 1000;
-  } test;
+    bool* const success_;
+  };
 
-  RunBaseTest(&test);
+  bool success;
+  const int kMaxAttempts = 3;
+  for (int i = 0; i < kMaxAttempts; ++i) {
+    InitialProbingTest test(&success);
+    RunBaseTest(&test);
+    if (success)
+      return;
+  }
+  RTC_DCHECK(success) << "Failed to perform mid initial probing ("
+                      << kMaxAttempts << " attempts).";
 }
 
 TEST_F(EndToEndTest, TriggerMidCallProbing) {
   class TriggerMidCallProbingTest : public ProbingTest {
    public:
-    TriggerMidCallProbingTest() : ProbingTest(300000) {}
+    explicit TriggerMidCallProbingTest(bool* success)
+        : ProbingTest(300000), success_(success) {}
 
     void PerformTest() override {
+      *success_ = false;
       int64_t start_time_ms = clock_->TimeInMilliseconds();
       do {
-        if (clock_->TimeInMilliseconds() - start_time_ms > kTimeoutMs) {
-          ADD_FAILURE() << "Timed out while waiting for mid-call probing.";
+        if (clock_->TimeInMilliseconds() - start_time_ms > kTimeoutMs)
           break;
-        }
 
         Call::Stats stats = sender_call_->GetStats();
 
@@ -2297,8 +2308,10 @@ TEST_F(EndToEndTest, TriggerMidCallProbing) {
             // During high cpu load the pacer will not be able to pace packets
             // at the correct speed, but if we go from 110 to 1250 kbps
             // in 5 seconds then it is due to probing.
-            if (stats.send_bandwidth_bps > 1250000)
+            if (stats.send_bandwidth_bps > 1250000) {
+              *success_ = true;
               observation_complete_.Set();
+            }
             break;
         }
       } while (!observation_complete_.Wait(20));
@@ -2306,9 +2319,19 @@ TEST_F(EndToEndTest, TriggerMidCallProbing) {
 
    private:
     const int kTimeoutMs = 5000;
-  } test;
+    bool* const success_;
+  };
 
-  RunBaseTest(&test);
+  bool success;
+  const int kMaxAttempts = 3;
+  for (int i = 0; i < kMaxAttempts; ++i) {
+    TriggerMidCallProbingTest test(&success);
+    RunBaseTest(&test);
+    if (success)
+      return;
+  }
+  RTC_DCHECK(success) << "Failed to perform mid call probing (" << kMaxAttempts
+                      << " attempts).";
 }
 
 TEST_F(EndToEndTest, VerifyNackStats) {