--- a/testing/remotecppunittests.py
+++ b/testing/remotecppunittests.py
@@ -6,16 +6,17 @@
 
 import os, sys
 import subprocess
 import tempfile
 from zipfile import ZipFile
 import runcppunittests as cppunittests
 import mozcrash
 import mozfile
+import mozinfo
 import StringIO
 import posixpath
 from mozdevice import devicemanager, devicemanagerADB, devicemanagerSUT
 from mozlog import structured
 
 try:
     from mozbuild.base import MozbuildObject
     build_obj = MozbuildObject.from_environment()
@@ -249,21 +250,18 @@ def main():
             sys.exit(1)
 
     log = structured.commandline.setup_logging("remotecppunittests",
                                                options,
                                                {"tbpl": sys.stdout})
 
 
     options.xre_path = os.path.abspath(options.xre_path)
-    if options.with_b2g_emulator:
-        environ = {'os': 'b2g'}
-    else:
-        environ = {'os': 'android'}
-    progs = cppunittests.extract_unittests_from_args(args, environ)
+    cppunittests.update_mozinfo()
+    progs = cppunittests.extract_unittests_from_args(args, mozinfo.info)
     tester = RemoteCPPUnitTests(dm, options, progs)
     try:
         result = tester.run_tests(progs, options.xre_path, options.symbols_path)
     except Exception, e:
         log.error(str(e))
         result = False
     if options.with_b2g_emulator:
         runner.cleanup()

--- a/testing/runcppunittests.py
+++ b/testing/runcppunittests.py
@@ -11,16 +11,18 @@ import manifestparser
 import mozprocess
 import mozinfo
 import mozcrash
 import mozfile
 from contextlib import contextmanager
 from mozlog import structured
 from subprocess import PIPE
 
+SCRIPT_DIR = os.path.abspath(os.path.realpath(os.path.dirname(__file__)))
+
 class CPPUnitTests(object):
     # Time (seconds) to wait for test process to complete
     TEST_PROC_TIMEOUT = 900
     # Time (seconds) in which process will be killed if it produces no output.
     TEST_PROC_NO_OUTPUT_TIMEOUT = 300
 
     def run_one_test(self, prog, env, symbols_path=None, interactive=False):
         """
@@ -195,31 +197,43 @@ def extract_unittests_from_args(args, en
     else:
         tests.extend([test['path'] for test in mp.active_tests(exists=False, disabled=False, **environ)])
 
     # skip non-existing tests
     tests = [test for test in tests if os.path.isfile(test)]
 
     return tests
 
+def update_mozinfo():
+    """walk up directories to find mozinfo.json update the info"""
+    path = SCRIPT_DIR
+    dirs = set()
+    while path != os.path.expanduser('~'):
+        if path in dirs:
+            break
+        dirs.add(path)
+        path = os.path.split(path)[0]
+    mozinfo.find_and_update_from_json(*dirs)
+
 def main():
     parser = CPPUnittestOptions()
     structured.commandline.add_logging_group(parser)
     options, args = parser.parse_args()
     if not args:
         print >>sys.stderr, """Usage: %s <test binary> [<test binary>...]""" % sys.argv[0]
         sys.exit(1)
     if not options.xre_path:
         print >>sys.stderr, """Error: --xre-path is required"""
         sys.exit(1)
 
     log = structured.commandline.setup_logging("cppunittests",
                                                options,
                                                {"tbpl": sys.stdout})
 
+    update_mozinfo()
     progs = extract_unittests_from_args(args, mozinfo.info)
     options.xre_path = os.path.abspath(options.xre_path)
     if mozinfo.isMac:
         options.xre_path = os.path.join(os.path.dirname(options.xre_path), 'Resources')
     tester = CPPUnitTests()
 
     try:
         result = tester.run_tests(progs, options.xre_path, options.symbols_path)

--- a/testing/testsuite-targets.mk
+++ b/testing/testsuite-targets.mk
@@ -512,16 +512,17 @@ stage-cppunittests: make-stage-dir
 ifdef STRIP_CPP_TESTS
 	$(foreach bin,$(CPP_UNIT_TEST_BINS),$(OBJCOPY) $(or $(STRIP_FLAGS),--strip-unneeded) $(bin) $(bin:$(DIST)/%=$(PKG_STAGE)/%);)
 else
 	cp -RL $(DIST)/cppunittests $(PKG_STAGE)
 endif
 	cp $(topsrcdir)/testing/runcppunittests.py $(PKG_STAGE)/cppunittests
 	cp $(topsrcdir)/testing/remotecppunittests.py $(PKG_STAGE)/cppunittests
 	cp $(topsrcdir)/testing/cppunittest.ini $(PKG_STAGE)/cppunittests
+	cp $(DEPTH)/mozinfo.json $(PKG_STAGE)/cppunittests
 ifeq ($(MOZ_DISABLE_STARTUPCACHE),)
 	cp $(topsrcdir)/startupcache/test/TestStartupCacheTelemetry.js $(PKG_STAGE)/cppunittests
 	cp $(topsrcdir)/startupcache/test/TestStartupCacheTelemetry.manifest $(PKG_STAGE)/cppunittests
 endif
 ifdef STRIP_CPP_TESTS
 	$(OBJCOPY) $(or $(STRIP_FLAGS),--strip-unneeded) $(DIST)/bin/jsapi-tests$(BIN_SUFFIX) $(PKG_STAGE)/cppunittests/jsapi-tests$(BIN_SUFFIX)
 else
 	cp -RL $(DIST)/bin/jsapi-tests$(BIN_SUFFIX) $(PKG_STAGE)/cppunittests