Move over to ABSL logging and flags.

Removes gperftools too since that wants gflags.

Here come the fireworks.

Change-Id: I79cb7bcf60f1047fbfa28bfffc21a0fd692e4b1c
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/y2021_bot3/BUILD b/y2021_bot3/BUILD
index 7d898f5..e3c70ff 100644
--- a/y2021_bot3/BUILD
+++ b/y2021_bot3/BUILD
@@ -30,8 +30,9 @@
         "//frc971/control_loops:pose",
         "//frc971/control_loops:static_zeroing_single_dof_profiled_subsystem",
         "//y2021_bot3/control_loops/drivetrain:polydrivetrain_plants",
-        "@com_github_google_glog//:glog",
         "@com_google_absl//absl/base",
+        "@com_google_absl//absl/log",
+        "@com_google_absl//absl/log:check",
     ],
 )
 
diff --git a/y2021_bot3/constants.cc b/y2021_bot3/constants.cc
index 63ebf7a..71b591b 100644
--- a/y2021_bot3/constants.cc
+++ b/y2021_bot3/constants.cc
@@ -8,7 +8,8 @@
 #endif
 
 #include "absl/base/call_once.h"
-#include "glog/logging.h"
+#include "absl/log/check.h"
+#include "absl/log/log.h"
 
 #include "aos/mutex/mutex.h"
 #include "aos/network/team_number.h"
diff --git a/y2021_bot3/control_loops/superstructure/superstructure_lib_test.cc b/y2021_bot3/control_loops/superstructure/superstructure_lib_test.cc
index 089250b..c40e616 100644
--- a/y2021_bot3/control_loops/superstructure/superstructure_lib_test.cc
+++ b/y2021_bot3/control_loops/superstructure/superstructure_lib_test.cc
@@ -1,6 +1,7 @@
 #include <chrono>
 #include <memory>
 
+#include "absl/flags/flag.h"
 #include "gtest/gtest.h"
 
 #include "aos/events/logging/log_writer.h"
@@ -10,8 +11,8 @@
 #include "frc971/control_loops/team_number_test_environment.h"
 #include "y2021_bot3/control_loops/superstructure/superstructure.h"
 
-DEFINE_string(output_folder, "",
-              "If set, logs all channels to the provided logfile.");
+ABSL_FLAG(std::string, output_folder, "",
+          "If set, logs all channels to the provided logfile.");
 
 namespace y2021_bot3::control_loops::superstructure::testing {
 
@@ -42,11 +43,11 @@
     phased_loop_handle_ = test_event_loop_->AddPhasedLoop(
         [this](int) { SendPositionMessage(); }, dt());
 
-    if (!FLAGS_output_folder.empty()) {
-      unlink(FLAGS_output_folder.c_str());
+    if (!absl::GetFlag(FLAGS_output_folder).empty()) {
+      unlink(absl::GetFlag(FLAGS_output_folder).c_str());
       logger_event_loop_ = MakeEventLoop("logger", roborio_);
       logger_ = std::make_unique<aos::logger::Logger>(logger_event_loop_.get());
-      logger_->StartLoggingOnRun(FLAGS_output_folder);
+      logger_->StartLoggingOnRun(absl::GetFlag(FLAGS_output_folder));
     }
   }