Adds the ability to run pure Go unit tests in the Mojo test suite.

mojo/tools/get_test_list.py

Index: mojo/tools/get_test_list.py
diff --git a/mojo/tools/get_test_list.py b/mojo/tools/get_test_list.py
index c59602c10244b174054ca4e0120d7a7db2ceaa19..8b0e177005e4946dfd1c3d094bde1f1d676bd0c3 100755
--- a/mojo/tools/get_test_list.py
+++ b/mojo/tools/get_test_list.py
@@ -117,9 +117,21 @@ def GetTestList(config, verbose_count=0):
   if (target_os == Config.OS_LINUX and
       config.sanitizer != Config.SANITIZER_ASAN and
       ShouldRunTest(Config.TEST_TYPE_DEFAULT, Config.TEST_TYPE_UNIT, "go")):
-    AddEntry("Go unit tests",
+
+    # Go system tests:
+    AddEntry("Go system tests",
              [os.path.join(build_dir, "obj", "mojo", "go", "system_test")])
 
+    # Pure Go unit tests:
+    if 'go_build_tool' in config.values:
+      go_tool = config.values['go_build_tool']
+    else:
+      go_tool = os.path.join(Paths().src_root, 'third_party', 'go', 'tool',
+        'linux_amd64', 'bin', 'go')
+    AddEntry("Go unit tests",
+            ["python", os.path.join("mojo", "tools", "run_pure_go_tests.py"),
+             "--go_tool=" + go_tool])
+
   # Python unit tests:
   if ShouldRunTest(Config.TEST_TYPE_DEFAULT, Config.TEST_TYPE_UNIT, "python"):
     AddEntry("Python unit tests",