Revert "[fuchsia] Collect Fuchsia system logs from Chrome-Fuchsia tests."

This reverts commit e2eb7388.

Reason for revert: Broke test_runner.py to not be able to run without
the --system-log-file parameter being set.

Original change's description:
> [fuchsia] Collect Fuchsia system logs from Chrome-Fuchsia tests.
> 
> The Fuchsia system logs contain more detailed information than the Fuchsia kernel logs.
> 
> Currently only Fuchsia kernel logs are collected.  The kernel logs are:
> - written to the swarming task output log along with the actual test output
> - optionally written to a "system_log" file in the test isolate output
> 
> This CL will:
> - optionally write the Fuchsia system log to a "log_listener_log" in the test isolate output
> 
> The Fuchsia system log will be written if the kernel log is written.
> 
> The Fuchsia system log is written to "log_listener_log".  The name "log_listener_log" was used because the Fuchsia kernel log contents are already saved in "system_log".
> 
> Bug: 1042512
> Change-Id: I900b5dfe9f6587f1901c19612060b979fae4da99
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2130679
> Reviewed-by: Kevin Marshall <kmarshall@chromium.org>
> Commit-Queue: Stephen Roe <steveroe@google.com>
> Cr-Commit-Position: refs/heads/master@{#756118}

TBR=wez@chromium.org,kmarshall@chromium.org,steveroe@google.com

Change-Id: I40d0b3030a86856717d53434ac58d7f85dce6fb0
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1042512
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2135686Reviewed-by: Wez <wez@chromium.org>
Commit-Queue: Wez <wez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#756217}

build/fuchsia/run_package.py

@@ -20,7 +20,6 @@ import time
 import threading
 import uuid
 
-from symbolizer import RunSymbolizer
 from symbolizer import SymbolizerFilter
 
 FAR = common.GetHostToolPathFromPlatform('far')
@@ -37,36 +36,6 @@ def _AttachKernelLogReader(target):
                                 stdout=subprocess.PIPE)
 
 
-def _BuildIdsPaths(package_paths):
-  """Generate build ids paths for symbolizer processes."""
-  build_ids_paths = map(
-      lambda package_path: os.path.join(
-          os.path.dirname(package_path), 'ids.txt'),
-      package_paths)
-  return build_ids_paths
-
-
-def StartSystemLogReader(target, package_paths, isolated_outputs_dir):
-  """Start a system log reader as a long-running SSH task.
-
-  Returns listener and symbolizer popen objects so that the caller can control
-  the popen process lifetimes."""
-  logging.info('Starting system log reader')
-
-  listener_proc = target.RunCommandPiped(['log_listener'],
-                                         stdout=subprocess.PIPE,
-                                         stderr=subprocess.STDOUT)
-
-  listener_log_path = os.path.join(isolated_outputs_dir, 'log_listener_log')
-  build_ids_paths = _BuildIdsPaths(package_paths)
-  listener_log = open(listener_log_path,'w', buffering=1)
-  symbolizer_proc = RunSymbolizer(listener_proc.stdout,
-                                  listener_log,
-                                  build_ids_paths)
-
-  return (listener_proc, symbolizer_proc)
-
-
 class MergedInputStream(object):
   """Merges a number of input streams into a UNIX pipe on a dedicated thread.
   Terminates when the file descriptor of the primary stream (the first in
@@ -225,7 +194,10 @@ def RunPackage(output_dir, target, package_paths, package_name,
         output_stream = process.stdout
 
       # Run the log data through the symbolizer process.
-      build_ids_paths = _BuildIdsPaths(package_paths)
+      build_ids_paths = map(
+          lambda package_path: os.path.join(
+              os.path.dirname(package_path), 'ids.txt'),
+          package_paths)
       output_stream = SymbolizerFilter(output_stream, build_ids_paths)
 
       for next_line in output_stream:

build/fuchsia/test_runner.py

@@ -18,7 +18,7 @@ import time
 
 from common_args import AddCommonArgs, ConfigureLogging, GetDeploymentTargetForArgs
 from net_test_server import SetupTestServer
-from run_package import RunPackage, RunPackageArgs, StartSystemLogReader
+from run_package import RunPackage, RunPackageArgs
 
 DEFAULT_TEST_SERVER_CONCURRENCY = 4
 
@@ -146,12 +146,6 @@ def main():
                      for_package=args.package_name)
       child_args.append('--test-launcher-filter-file=' + TEST_FILTER_PATH)
 
-    isolated_outputs_dir = os.path.dirname(args.system_log_file)
-    if os.path.isdir(isolated_outputs_dir):
-      # Store logging popen objects so that they live as long as the target.
-      system_log_procs = StartSystemLogReader(target, args.package,
-                                              isolated_outputs_dir)
-
     test_server = None
     if args.enable_test_server:
       assert test_concurrency