[CT] Change mount path and add missing required libraries

Bug: chromium:990725
Change-Id: I1f033395cb8438698eba5df7a212604e07e13615
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/233856
Reviewed-by: Ravi Mistry <rmistry@google.com>
Commit-Queue: Ravi Mistry <rmistry@google.com>
diff --git a/go/gce/ct/instance_types/instance_types.go b/go/gce/ct/instance_types/instance_types.go
index b9e42c5..4ec7656 100644
--- a/go/gce/ct/instance_types/instance_types.go
+++ b/go/gce/ct/instance_types/instance_types.go
@@ -29,7 +29,7 @@
 		Name:      fmt.Sprintf("%s-data", name),
 		SizeGb:    300,
 		Type:      gce.DISK_TYPE_PERSISTENT_STANDARD,
-		MountPath: "/mnt/pd0",
+		MountPath: "/b",
 	}
 	if useSSDDataDisk {
 		dataDisk.Type = gce.DISK_TYPE_PERSISTENT_SSD
diff --git a/go/gce/ct/setup-script.sh b/go/gce/ct/setup-script.sh
index b76aa96..6800d51 100644
--- a/go/gce/ct/setup-script.sh
+++ b/go/gce/ct/setup-script.sh
@@ -10,7 +10,7 @@
 sudo apt-get update
 sudo apt-get -y install libosmesa-dev clang-3.6 poppler-utils netpbm \
     python-django libgif-dev lua5.2 libnss3 python-setuptools python-pip \
-    libglu1 libgtk3.0 xvfb
+    libglu1 libgtk3.0 xvfb gperf bison
 sudo pip install -U crcmod mock psutil
 
 # Install openjdk-8. See skbug.com/6975 for context.
@@ -39,12 +39,6 @@
 fi
 PATH=$PATH:~/depot_tools
 
-# Create /b if it does not already exist.
-if [[ ! -d /b ]]; then
-  sudo mkdir /b
-  sudo chown chrome-bot:chrome-bot /b
-fi
-
 # If the bot is a builder then checkout Chromium and Skia repositories.
 if [[ $(hostname -s) = ct-*-builder* ]]; then
   echo "Checking out Chromium repository..."