Waiting for broadcasts idle in TaplInstrumentation constructor

Hoping that this will prevent Launcher restarts
during test execution.

Test: presubmit
Bug: 187761685
Change-Id: If9ba8795bcb27366dd1b2cdcad1c5329ef2e76c0
diff --git a/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java b/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java
index c4d46ee..71f52fd 100644
--- a/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java
+++ b/tests/tapl/com/android/launcher3/tapl/LauncherInstrumentation.java
@@ -207,6 +207,11 @@
     public LauncherInstrumentation(Instrumentation instrumentation) {
         mInstrumentation = instrumentation;
         mDevice = UiDevice.getInstance(instrumentation);
+        try {
+            mDevice.executeShellCommand("am wait-for-broadcast-idle");
+        } catch (IOException e) {
+            log("Failed to wait for broadcast idle");
+        }
 
         // Launcher should run in test harness so that custom accessibility protocol between
         // Launcher and TAPL is enabled. In-process tests enable this protocol with a direct call