SysrootService: Add portage binhost logging.

The portage binhost is an important piece of information for a
lot of problems. Add logging to the two endpoints where the
problems most often manifest.

BUG=None
TEST=run_tests

Change-Id: I584eebde319134198be28ca427ce0957794da942
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1618205
Tested-by: Sean Abraham <seanabraham@chromium.org>
Commit-Queue: Sean Abraham <seanabraham@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
diff --git a/api/controller/sysroot_unittest.py b/api/controller/sysroot_unittest.py
index 35c0f55..6e9e4c4 100644
--- a/api/controller/sysroot_unittest.py
+++ b/api/controller/sysroot_unittest.py
@@ -108,6 +108,8 @@
 
   def setUp(self):
     self.PatchObject(cros_build_lib, 'IsInsideChroot', return_value=True)
+    # Avoid running the portageq command.
+    self.PatchObject(sysroot_controller, '_LogBinhost')
     self.board = 'board'
     self.sysroot = os.path.join(self.tempdir, 'board')
     self.invalid_sysroot = os.path.join(self.tempdir, 'invalid', 'sysroot')
@@ -194,6 +196,8 @@
 
   def setUp(self):
     self.PatchObject(cros_build_lib, 'IsInsideChroot', return_value=True)
+    # Avoid running the portageq command.
+    self.PatchObject(sysroot_controller, '_LogBinhost')
     self.build_target = 'board'
     self.sysroot = os.path.join(self.tempdir, 'build', 'board')
     osutils.SafeMakedirs(self.sysroot)