tools_common.sh: Allow over ride of test name.

Use VPX_TEST_NAME instead of the script name sans path and extension
when reporting test results when the variable is not empty.

Also: Clean up some style nits while I'm at it.

Change-Id: I0319745a3b7a90d0f307e55c5108fea2204187cd
diff --git a/test/tools_common.sh b/test/tools_common.sh
index 9c10d48..472111c 100755
--- a/test/tools_common.sh
+++ b/test/tools_common.sh
@@ -302,8 +302,13 @@
 # functions and are run unconditionally. Functions in positional parameter two
 # are run according to the rules specified in vpx_test_usage().
 run_tests() {
-  env_tests="verify_vpx_test_environment ${1}"
-  tests_to_filter="${2}"
+  local env_tests="verify_vpx_test_environment $1"
+  local tests_to_filter="$2"
+  local test_name="${VPX_TEST_NAME}"
+
+  if [ -z "${test_name}" ]; then
+    test_name="$(basename \"${0%.*}\")"
+  fi
 
   if [ "${VPX_TEST_RUN_DISABLED_TESTS}" != "yes" ]; then
     # Filter out DISABLED tests.
@@ -315,7 +320,7 @@
     tests_to_filter=$(filter_strings "${tests_to_filter}" ${VPX_TEST_FILTER})
   fi
 
-  tests_to_run="${env_tests} ${tests_to_filter}"
+  local tests_to_run="${env_tests} ${tests_to_filter}"
 
   check_git_hashes
 
@@ -328,8 +333,8 @@
     test_end "${test}"
   done
 
-  tested_config="$(test_configuration_target) @ $(current_hash)"
-  echo $(basename "${0%.*}"): Done, all tests pass for ${tested_config}.
+  local tested_config="$(test_configuration_target) @ $(current_hash)"
+  echo "${test_name}: Done, all tests pass for ${tested_config}."
 }
 
 vpx_test_usage() {