[ChromeDriver] Fix Chromedriver functioning for Android O

In Android O "ps" only returns the user's processes (generally just the "ps"
command itself). Run both the bare "ps" command and with the flag "-A" to
handle Android O.

Move to using ps && ps -A for chromedriver process inspection

Bug: chromedriver:2013
Change-Id: I1cc667f2ec6ff9ac5363ad7f8d34614a16badf3b
Reviewed-on: https://chromium-review.googlesource.com/696163Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: John Chen <johnchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#505817}

AUTHORS

@@ -304,6 +304,7 @@ Ilia K <ki.stfu@gmail.com>
 Ilya Konstantinov <ilya.konstantinov@gmail.com>
 Ion Rosca <rosca@adobe.com>
 Irmak Kavasoglu <irmakkavasoglu@gmail.com>
+Isaac Murchie <murchieisaac@gmail.com>
 Isaac Reilly <reillyi@amazon.com>
 Ivan Sham <ivansham@amazon.com>
 J. Ryan Stinnett <jryans@chromium.org>

chrome/test/chromedriver/chrome/adb_impl.cc

@@ -206,7 +206,10 @@ Status AdbImpl::GetPidByName(const std::string& device_serial,
                              const std::string& process_name,
                              int* pid) {
   std::string response;
-  Status status = ExecuteHostShellCommand(device_serial, "ps", &response);
+  // on Android O `ps` returns only user processes, so also try with `-A` flag.
+  Status status = ExecuteHostShellCommand(device_serial, "ps && ps -A",
+      &response);
+
   if (!status.IsOk())
     return status;
 
@@ -263,4 +266,3 @@ Status AdbImpl::ExecuteHostShellCommand(
       "host:transport:" + device_serial + "|shell:" + shell_command,
       response);
 }
-