Cannot compile from source files downloaded from the website

[mavanmanen]

Here is the output:

$ make
Making kb with keymap default

avr-gcc.exe (AVR_8_bit_GNU_Toolchain_3.5.4_1709) 4.9.2
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Compiling: keyboards/kb/kb.c                                                                        [OK]
Compiling: keyboards/kb/keymaps/default/keymap.c                                                   keyboards/kb/keymaps/default/keymap.c: In function 'action_get_macro':
keyboards/kb/keymaps/default/keymap.c:104:13: warning: unused variable 'event' [-Wunused-variable]
  keyevent_t event = record->event;
             ^
 [OK]
Compiling: quantum/quantum.c                                                                        [OK]
Compiling: quantum/keymap_common.c                                                                  [OK]
Compiling: quantum/keycode_config.c                                                                 [OK]
Compiling: quantum/process_keycode/process_leader.c                                                 [OK]
Compiling: quantum/matrix.c                                                                         [OK]
Compiling: quantum/light_ws2812.c                                                                   [OK]
Compiling: quantum/rgblight.c                                                                       [OK]
Compiling: ./tmk_core/common/host.c                                                                 [OK]
Compiling: ./tmk_core/common/keyboard.c                                                             [OK]
Compiling: ./tmk_core/common/action.c                                                               [OK]
Compiling: ./tmk_core/common/action_tapping.c                                                       [OK]
Compiling: ./tmk_core/common/action_macro.c                                                         [OK]
Compiling: ./tmk_core/common/action_layer.c                                                         [OK]
Compiling: ./tmk_core/common/action_util.c                                                          [OK]
Compiling: ./tmk_core/common/print.c                                                                [OK]
Compiling: ./tmk_core/common/debug.c                                                                [OK]
Compiling: ./tmk_core/common/util.c                                                                 [OK]
Compiling: ./tmk_core/common/eeconfig.c                                                             [OK]
Compiling: ./tmk_core/common/avr/suspend.c                                                          [OK]
Compiling: ./tmk_core/common/avr/timer.c                                                            [OK]
Compiling: ./tmk_core/common/avr/bootloader.c                                                       [OK]
Assembling: ./tmk_core/common/avr/xprintf.S                                                         [OK]
Compiling: ./tmk_core/common/bootmagic.c                                                            [OK]
Compiling: ./tmk_core/common/mousekey.c                                                             [OK]
Compiling: ./tmk_core/common/backlight.c                                                            [OK]
Compiling: ./tmk_core/protocol/lufa/lufa.c                                                          [OK]
Compiling: ./tmk_core/protocol/lufa/descriptor.c                                                    [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Class/Common/HIDParser.c              [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/Device_AVR8.c               [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/EndpointStream_AVR8.c       [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/Endpoint_AVR8.c             [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/Host_AVR8.c                 [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/PipeStream_AVR8.c           [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/Pipe_AVR8.c                 [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/USBController_AVR8.c        [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/AVR8/USBInterrupt_AVR8.c         [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/ConfigDescriptors.c              [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/DeviceStandardReq.c              [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/Events.c                         [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/HostStandardReq.c                [OK]
Compiling: ./tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/USB/Core/USBTask.c                        [OK]
Linking: .build/kb_default.elf                                                                      [OK]
Creating load file for Flash: .build/kb_default.hex                                                 [OK]

Size after:
   text    data     bss     dec     hex filename
      0   21898       0   21898    558a kb_default.hex

Making test serial_link_byte_stuffer                                                                           [ERRORS]
quantum/serial_link/tests/byte_stuffer_tests.cpp:25:25: fatal error: gtest/gtest.h: No such file or directory
 #include "gtest/gtest.h"
                         ^
compilation terminated.
 |
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 |
make[1]: *** [tmk_core/rules.mk:355: .build/test_obj/serial_link_byte_stuffer/./quantum/serial_link/tests/byte_stuffer_tests.o] Error 1
Making test serial_link_frame_validator                                                                        [ERRORS]
quantum/serial_link/tests/frame_validator_tests.cpp:25:25: fatal error: gtest/gtest.h: No such file or directory
 #include "gtest/gtest.h"
                         ^
compilation terminated.
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make[1]: *** [tmk_core/rules.mk:355: .build/test_obj/serial_link_frame_validator/./quantum/serial_link/tests/frame_validator_tests.o] Error 1
Making test serial_link_frame_router                                                                           [ERRORS]
quantum/serial_link/tests/frame_router_tests.cpp:25:25: fatal error: gtest/gtest.h: No such file or directory
 #include "gtest/gtest.h"
                         ^
compilation terminated.
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make[1]: *** [tmk_core/rules.mk:355: .build/test_obj/serial_link_frame_router/./quantum/serial_link/tests/frame_router_tests.o] Error 1
Making test serial_link_triple_buffered_object                                                                 [ERRORS]
quantum/serial_link/tests/triple_buffered_object_tests.cpp:25:25: fatal error: gtest/gtest.h: No such file or directory
 #include "gtest/gtest.h"
                         ^
compilation terminated.
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make[1]: *** [tmk_core/rules.mk:355: .build/test_obj/serial_link_triple_buffered_object/./quantum/serial_link/tests/triple_buffered_object_tests.o] Error 1
Making test serial_link_transport                                                                              [ERRORS]
quantum/serial_link/tests/transport_tests.cpp:25:25: fatal error: gtest/gtest.h: No such file or directory
 #include "gtest/gtest.h"
                         ^
compilation terminated.
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make[1]: *** [tmk_core/rules.mk:355: .build/test_obj/serial_link_transport/./quantum/serial_link/tests/transport_tests.o] Error 1
Make finished with errors
make: *** [Makefile:501: test-all] Error 1