autoninja: quote the arguments when needed.

On Windows, without quote, whole return value would be treated as
a command, and the execution would fail.
On Linux and Mac, without quote, if depot_tools is settled under
directories with ' ', command execution would fail because paths are
separated in a wrong way.

To make such a return value work on Linux and Mac, the shell script
started to use eval.

Bug: 902930
Change-Id: I9bb74585294af565988c0b844b6b113a5c685530
Reviewed-on: https://chromium-review.googlesource.com/c/1325249Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Yoshisato Yanagisawa <yyanagisawa@chromium.org>

autoninja

@@ -11,7 +11,7 @@ export AUTONINJA_BUILD_ID="$(python -c "import uuid; print uuid.uuid4()")"
 # Also print it to reassure that the right settings are being used.
 command=$(python $(dirname -- "$0")/autoninja.py "$@")
 echo $command
-$command
+eval $command
 if [ $? -eq 0 ]; then
   if [ "$NINJA_SUMMARIZE_BUILD" == "1" ]; then
     python $(dirname -- "$0")/post_build_ninja_summary.py $@

autoninja.py

@@ -69,14 +69,8 @@ except IOError:
 # Specify ninja.exe on Windows so that ninja.bat can call autoninja and not
 # be called back.
 ninja_exe = 'ninja.exe' if sys.platform.startswith('win') else 'ninja'
-
 ninja_exe_path = os.path.join(SCRIPT_DIR, ninja_exe)
 
-# On Windows, fully quote the path so that the command processor doesn't think
-# the whole output is the command.
-if sys.platform.startswith('win'):
-  ninja_exe_path = '"' + ninja_exe_path + '"'
-
 # Use absolute path for ninja path,
 # or fail to execute ninja if depot_tools is not in PATH.
 args = [ninja_exe_path] + input_args[1:]
@@ -94,4 +88,14 @@ if not j_specified and not t_specified:
       args.append('-j')
       args.append('%d' % (num_cores + core_addition))
 
+# On Windows, fully quote the path so that the command processor doesn't think
+# the whole output is the command.
+# On Linux and Mac, if people put depot_tools in directories with ' ',
+# shell would misunderstand ' ' as a path separation.
+# TODO(yyanagisawa): provide proper quating for Windows.
+# see https://cs.chromium.org/chromium/src/tools/mb/mb.py
+for i in range(len(args)):
+  if (i == 0 and sys.platform.startswith('win')) or ' ' in args[i]:
+    args[i] = '"%s"' % args[i].replace('"', '\\"')
+
 print ' '.join(args)