Add an option for disabling java assertions.

build/android/pylib/run_java_tests.py

Index: build/android/pylib/run_java_tests.py
diff --git a/build/android/pylib/run_java_tests.py b/build/android/pylib/run_java_tests.py
index fc0a13fd8120323d9f31ff0fef78105fae49cb4d..7c7d11f6db15553b755f035874720bc3a1f9e702 100644
--- a/build/android/pylib/run_java_tests.py
+++ b/build/android/pylib/run_java_tests.py
@@ -95,6 +95,7 @@ class TestRunner(BaseTestRunner):
       -  screenshot_failures: Take a screenshot for a test failure
       -  tool: Name of the Valgrind tool.
       -  wait_for_debugger: blocks until the debugger is connected.
+      -  disable_assertions: Whether to disable java assertions on the device.
       device: Attached android device.
       tests_iter: A list of tests to be run.
       coverage: Collects coverage information if opted.
@@ -120,6 +121,7 @@ class TestRunner(BaseTestRunner):
     self.save_perf_json = options.save_perf_json
     self.screenshot_failures = options.screenshot_failures
     self.wait_for_debugger = options.wait_for_debugger
+    self.disable_assertions = options.disable_assertions
 
     self.tests_iter = tests_iter
     self.coverage = coverage
@@ -262,7 +264,7 @@ class TestRunner(BaseTestRunner):
       logging.warning('Unable to enable java asserts for %s, non rooted device',
                       self.device)
     else:
-      if self.adb.SetJavaAssertsEnabled(enable=True):
+      if self.adb.SetJavaAssertsEnabled(enable=not self.disable_assertions):
         self.adb.Reboot(full_reboot=False)
 
     # We give different default value to launch HTTP server based on shard index