Revert of tools/battor_agent: Adds a tool to find connected BattOrs (patchset #3 id:40001 of https://codereview.chromium.org/1611533002/ )

Reason for revert:
buildbot failure in Chromium GPU on Android Debug (Nexus 6)

[918/3714] LINK battor_agent
...
obj/tools/battor_agent/libbattor_agent_lib.a(obj/tools/battor_agent/battor_agent_lib.battor_finder.o):battor_finder.cc:function battor::BattOrFinder::FindBattOr(): error: undefined reference to 'device::SerialDeviceEnumerator::Create()'

Original issue's description:
> tools/battor_agent: Adds a tool to find connected BattOrs
>
> This tool will also be used by the Chromium trace controller to find
> any connected BattOrs.
>
> BUG=542837
>
> Committed: https://crrev.com/22f5284d4b0e007cb59effaefa7dbd82717eca79
> Cr-Commit-Position: refs/heads/master@{#370985}

TBR=zhenw@chromium.org,nednguyen@google.com,sky@chromium.org,charliea@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=542837

Review URL: https://codereview.chromium.org/1623563002

Cr-Commit-Position: refs/heads/master@{#370992}

6 files changed, 4 insertions, 87 deletions

diff --git a/tools/battor_agent/BUILD.gn b/tools/battor_agent/BUILD.gn
index 1a057f3..2f6dd28 100644
--- a/tools/battor_agent/BUILD.gn
+++ b/tools/battor_agent/BUILD.gn
@@ -28,8 +28,6 @@ source_set("battor_agent_lib") {
     "battor_connection_impl.cc",
     "battor_connection_impl.h",
     "battor_error.h",
-    "battor_finder.cc",
-    "battor_finder.h",
     "battor_sample_converter.cc",
     "battor_sample_converter.h",
   ]
diff --git a/tools/battor_agent/DEPS b/tools/battor_agent/DEPS
index b40de52..67358f38 100644
--- a/tools/battor_agent/DEPS
+++ b/tools/battor_agent/DEPS
@@ -1,5 +1,4 @@
 include_rules = [
   "+device/serial",
-  "+mojo/public",
   "+net/base",
 ]
\ No newline at end of file
diff --git a/tools/battor_agent/battor_agent.gyp b/tools/battor_agent/battor_agent.gyp
index c34c5cd..051f66d 100644
--- a/tools/battor_agent/battor_agent.gyp
+++ b/tools/battor_agent/battor_agent.gyp
@@ -35,8 +35,6 @@
         'battor_connection_impl.cc',
         'battor_connection_impl.h',
         'battor_error.h',
-        'battor_finder.cc',
-        'battor_finder.h',
         'battor_sample_converter.cc',
         'battor_sample_converter.h',
       ],
diff --git a/tools/battor_agent/battor_agent_bin.cc b/tools/battor_agent/battor_agent_bin.cc
index 93036e2..360146d 100644
--- a/tools/battor_agent/battor_agent_bin.cc
+++ b/tools/battor_agent/battor_agent_bin.cc
@@ -19,7 +19,6 @@
 #include "base/threading/thread.h"
 #include "tools/battor_agent/battor_agent.h"
 #include "tools/battor_agent/battor_error.h"
-#include "tools/battor_agent/battor_finder.h"
 
 using std::cout;
 using std::endl;
@@ -48,11 +47,12 @@ void PrintSupportsExplicitClockSync() {
   cout << battor::BattOrAgent::SupportsExplicitClockSync() << endl;
 }
 
-// Retrieves argument argnum from the argument list, or an empty string if the
-// argument doesn't exist.
+// Retrieves argument argnum from the argument list, printing the usage
+// guidelines and exiting with an error code if the argument doesn't exist.
 std::string GetArg(int argnum, int argc, char* argv[]) {
   if (argnum >= argc) {
-    return std::string();
+    PrintUsage();
+    exit(1);
   }
 
   return argv[argnum];
@@ -89,10 +89,6 @@ class BattOrAgentBin : public BattOrAgent::Listener {
   // Runs the BattOr binary and returns the exit code.
   int Run(int argc, char* argv[]) {
     std::string cmd = GetArg(1, argc, argv);
-    if (cmd.empty()) {
-      PrintUsage();
-      exit(1);
-    }
 
     // SupportsExplicitClockSync doesn't need to use the serial connection, so
     // handle it separately.
@@ -102,18 +98,6 @@ class BattOrAgentBin : public BattOrAgent::Listener {
     }
 
     std::string path = GetArg(2, argc, argv);
-    // If no path is specified, see if we can find a BattOr and use that.
-    if (path.empty())
-      path = BattOrFinder::FindBattOr();
-
-    // If we don't have any BattOr to use, exit.
-    if (path.empty()) {
-      cout << "Unable to find a BattOr, and no explicit BattOr path was "
-              "specified."
-           << endl;
-      exit(1);
-    }
-
     SetUp(path);
 
     if (cmd == "StartTracing") {
diff --git a/tools/battor_agent/battor_finder.cc b/tools/battor_agent/battor_finder.cc
deleted file mode 100644
index b0e32db..0000000
--- a/tools/battor_agent/battor_finder.cc
+++ /dev/null
@@ -1,39 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "tools/battor_agent/battor_finder.h"
-
-#include "device/serial/serial.mojom.h"
-#include "device/serial/serial_device_enumerator.h"
-#include "mojo/public/cpp/bindings/array.h"
-
-namespace battor {
-
-namespace {
-
-// The USB display name prefix that all BattOrs have.
-const char kBattOrDisplayNamePrefix[] = "BattOr";
-
-}  // namespace
-
-// Returns the path of the first BattOr that we find.
-std::string BattOrFinder::FindBattOr() {
-  scoped_ptr<device::SerialDeviceEnumerator> serial_device_enumerator =
-      device::SerialDeviceEnumerator::Create();
-
-  mojo::Array<device::serial::DeviceInfoPtr> devices =
-      serial_device_enumerator->GetDevices();
-
-  for (size_t i = 0; i < devices.size(); i++) {
-    std::string display_name = devices[i]->display_name.get();
-
-    if (display_name.find(kBattOrDisplayNamePrefix) != std::string::npos) {
-      return devices[i]->path;
-    }
-  }
-
-  return std::string();
-}
-
-}  // namespace battor
diff --git a/tools/battor_agent/battor_finder.h b/tools/battor_agent/battor_finder.h
deleted file mode 100644
index fe6fa79..0000000
--- a/tools/battor_agent/battor_finder.h
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef TOOLS_BATTOR_AGENT_BATTOR_FINDER_H_
-#define TOOLS_BATTOR_AGENT_BATTOR_FINDER_H_
-
-#include <string>
-
-#include "base/macros.h"
-
-namespace battor {
-
-class BattOrFinder {
- public:
-  static std::string FindBattOr();
-
-  DISALLOW_COPY_AND_ASSIGN(BattOrFinder);
-};
-
-}  // namespace battor
-
-#endif  // TOOLS_BATTOR_AGENT_BATTOR_FINDER_H_