[ChromeDriver] Add --log-level command line switch

Add a new command line switch for ChromeDriver, to allow more
flexibility in controlling the log level.

Bug: chromedriver:2221
Change-Id: I788c56d823d7d63b9f65ce31105230d2ffa47887
Reviewed-on: https://chromium-review.googlesource.com/912589
Commit-Queue: John Chen <johnchen@chromium.org>
Reviewed-by: Jonathon Kereliuk <kereliuk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539539}

chrome/test/chromedriver/chrome_launcher.cc

@@ -377,7 +377,9 @@ Status LaunchDesktopChrome(URLRequestContextGetter* context_getter,
 
 #if defined(OS_POSIX)
   base::ScopedFD devnull;
-  if (!base::CommandLine::ForCurrentProcess()->HasSwitch("verbose")) {
+  const base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();
+  if (!cmd_line->HasSwitch("verbose") &&
+      cmd_line->GetSwitchValueASCII("log-level") != "ALL") {
     // Redirect stderr to /dev/null, so that Chrome log spew doesn't confuse
     // users.
     devnull.reset(HANDLE_EINTR(open("/dev/null", O_WRONLY)));

chrome/test/chromedriver/logging.cc

@@ -253,11 +253,32 @@ bool InitLogging() {
       return false;
     }
   }
-  if (cmd_line->HasSwitch("silent"))
+
+  int num_level_switches = 0;
+
+  if (cmd_line->HasSwitch("silent")) {
     g_log_level = Log::kOff;
+    num_level_switches++;
+  }
 
-  if (cmd_line->HasSwitch("verbose"))
+  if (cmd_line->HasSwitch("verbose")) {
     g_log_level = Log::kAll;
+    num_level_switches++;
+  }
+
+  if (cmd_line->HasSwitch("log-level")) {
+    if (!WebDriverLog::NameToLevel(cmd_line->GetSwitchValueASCII("log-level"),
+                                   &g_log_level)) {
+      printf("Invalid --log-level value.\n");
+      return false;
+    }
+    num_level_switches++;
+  }
+
+  if (num_level_switches > 1) {
+    printf("Only one of --log-level, --verbose, or --silent is allowed.\n");
+    return false;
+  }
 
   // Turn on VLOG for chromedriver. This is parsed during logging::InitLogging.
   cmd_line->AppendSwitchASCII("vmodule", "*/chrome/test/chromedriver/*=3");

chrome/test/chromedriver/server/chromedriver_server.cc

@@ -256,9 +256,11 @@ int main(int argc, char *argv[]) {
         "adb-port=PORT", "adb server port",
         "log-path=FILE", "write server log to file instead of stderr, "
             "increases log level to INFO",
-        "verbose", "log verbosely",
+        "log-level=LEVEL", "set log level: ALL, DEBUG, INFO, WARNING, "
+            "SEVERE, OFF",
+        "verbose", "log verbosely (equivalent to --log-level=ALL)",
+        "silent", "log nothing (equivalent to --log-level=OFF)",
         "version", "print the version number and exit",
-        "silent", "log nothing",
         "url-base", "base URL path prefix for commands, e.g. wd/url",
         "port-server", "address of server to contact for reserving a port",
         "whitelisted-ips", "comma-separated whitelist of remote IPv4 addresses "
@@ -321,7 +323,8 @@ int main(int argc, char *argv[]) {
     whitelisted_ips = base::SplitString(
         whitelist, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
   }
-  if (!cmd_line->HasSwitch("silent")) {
+  if (!cmd_line->HasSwitch("silent") &&
+      cmd_line->GetSwitchValueASCII("log-level") != "OFF") {
     printf("Starting ChromeDriver %s on port %u\n", kChromeDriverVersion, port);
     if (!allow_remote) {
       printf("Only local connections are allowed.\n");