Running tests in service of https://codereview.chromium.org/2735443002/

build_args.log

$ cat out/Default/args.gn 
# Build arguments go here. Examples:
#   is_component_build = true
#   is_debug = false
# See "gn args <out_dir> --list" for available build arguments.
enable_nacl = false
symbol_level = 0
remove_webcore_debug_symbols = true
is_debug = false

out.log

$ third_party/WebKit/Tools/Scripts/run-webkit-tests --target=Default --no-retry-failures virtual/service-worker-navigation-preload-wpt/external/wpt/service-workers/service-worker/navigation-preload/
Using port 'linux-trusty'
Test configuration: <trusty, x86_64, release>
View the test results at file:///home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/layout-test-results/results.html
View the archived results dashboard at file:///home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/layout-test-results/dashboard.html
Using random order with seed: 1489519568
Baseline search path: linux -> win -> generic
Using Release build
Pixel tests enabled
Regular timeout: 6000, slow test timeout: 30000
Command line: /home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/content_shell --run-layout-test --enable-crash-reporter --crash-dumps-dir=/home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/crash-dumps -

Found 4 tests; running 4, skipping 0.              
Unable to find test driver
    at /home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/content_shell
image_diff was not found at /home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/image_diff
Unable to find dump_syms
    at /home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/dump_syms
Unable to find minidump_stackwalk
    at /home/mike/projects/bocoup/google-wpt/chromium/src/out/Default/minidump_stackwalk
    Could not find breakpad tools, unexpected crashes won't be symbolized
    Did you build the target blink_tests?

For complete Linux build requirements, please see:

    https://chromium.googlesource.com/chromium/src/+/master/docs/linux_build_instructions.md
Build check failed