Bug 1580129 - Handle external metrics in TelemetryTest. r=snorp

Right now testOnTelemetryReceived assumes that only the test histograms will
fire during the test. This works because only the test histograms are enabled
for streaming telemetry and will break as soon as some other histogram is
enabled.

Instead of relying on this fact we just wait for the test histogram to fire and
ignore all the other unrelated ones.

Differential Revision: https://phabricator.services.mozilla.com/D47015

--HG--
extra : moz-landing-system : lando

mobile/android/geckoview/src/androidTest/java/org/mozilla/geckoview/test/TelemetryTest.kt

@@ -6,7 +6,6 @@ package org.mozilla.geckoview.test
 
 import android.support.test.filters.MediumTest
 import android.support.test.runner.AndroidJUnit4
-import android.util.Log
 import org.hamcrest.CoreMatchers.equalTo
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -19,13 +18,6 @@ import org.mozilla.geckoview.test.rule.GeckoSessionTestRule.AssertCalled
 class TelemetryTest : BaseSessionTest() {
     @Test
     fun testOnTelemetryReceived() {
-        sessionRule.addExternalDelegateUntilTestEnd(
-            RuntimeTelemetry.Delegate::class,
-                sessionRule::setTelemetryDelegate,
-                { sessionRule.setTelemetryDelegate(null) },
-                object : RuntimeTelemetry.Delegate {}
-        )
-
         // Let's make sure we batch the two telemetry calls
         sessionRule.setPrefsUntilTestEnd(
                 mapOf("toolkit.telemetry.geckoview.batchDurationMS" to 100000))
@@ -39,44 +31,70 @@ class TelemetryTest : BaseSessionTest() {
         sessionRule.setScalar("telemetry.test.unsigned_int_kind", 1234)
         sessionRule.setScalar("telemetry.test.string_kind", "test scalar")
 
-        // Forces flushing telemetry data at next histogram
-        sessionRule.setPrefsUntilTestEnd(mapOf("toolkit.telemetry.geckoview.batchDurationMS" to 0))
-        sessionRule.addHistogram("TELEMETRY_TEST_STREAMING", 2000)
+        val histogram = GeckoResult<Void>()
+        val stringScalar = GeckoResult<Void>()
+        val booleanScalar = GeckoResult<Void>()
+        val longScalar = GeckoResult<Void>()
 
-        sessionRule.waitUntilCalled(object : RuntimeTelemetry.Delegate {
+        sessionRule.addExternalDelegateUntilTestEnd(
+                RuntimeTelemetry.Delegate::class,
+                sessionRule::setTelemetryDelegate,
+                { sessionRule.setTelemetryDelegate(null) },
+                object : RuntimeTelemetry.Delegate {
             @AssertCalled
             override fun onHistogram(metric: RuntimeTelemetry.Histogram) {
-                assertThat("Metric name should be correct", metric.name,
-                        equalTo("TELEMETRY_TEST_STREAMING"))
+                if (metric.name != "TELEMETRY_TEST_STREAMING") {
+                    return
+                }
+
                 assertThat("Metric name should be correct", metric.value,
                         equalTo(longArrayOf(401, 12, 1, 109, 2000)))
                 assertThat("The histogram should not be categorical", metric.isCategorical,
                         equalTo(false))
+                histogram.complete(null)
             }
 
             @AssertCalled
             override fun onStringScalar(metric: RuntimeTelemetry.Metric<String>) {
-                assertThat("Metric name should be correct", metric.name,
-                        equalTo("telemetry.test.string_kind"))
+                if (metric.name != "telemetry.test.string_kind") {
+                    return
+                }
+
                 assertThat("Metric name should be correct", metric.value,
                         equalTo("test scalar"))
+                stringScalar.complete(null)
             }
 
             @AssertCalled
             override fun onBooleanScalar(metric: RuntimeTelemetry.Metric<Boolean>) {
-                assertThat("Metric name should be correct", metric.name,
-                        equalTo("telemetry.test.boolean_kind"))
+                if (metric.name != "telemetry.test.boolean_kind") {
+                    return
+                }
+
                 assertThat("Metric name should be correct", metric.value,
                         equalTo(true))
+                booleanScalar.complete(null)
             }
 
             @AssertCalled
             override fun onLongScalar(metric: RuntimeTelemetry.Metric<Long>) {
-                assertThat("Metric name should be correct", metric.name,
-                        equalTo("telemetry.test.unsigned_int_kind"))
+                if (metric.name != "telemetry.test.unsigned_int_kind") {
+                    return
+                }
+
                 assertThat("Metric name should be correct", metric.value,
                         equalTo(1234L))
+                longScalar.complete(null)
             }
         })
+
+        // Forces flushing telemetry data at next histogram
+        sessionRule.setPrefsUntilTestEnd(mapOf("toolkit.telemetry.geckoview.batchDurationMS" to 0))
+        sessionRule.addHistogram("TELEMETRY_TEST_STREAMING", 2000)
+
+        sessionRule.waitForResult(histogram)
+        sessionRule.waitForResult(stringScalar)
+        sessionRule.waitForResult(booleanScalar)
+        sessionRule.waitForResult(longScalar)
     }
 }