Replace which by bash-builtin hash

Reportedly, which is not installed by default on all non-windows
systems bazel is used. As we only use which to test if a program
can be found on PATH, use the bash builtin hash command. While there
- replace the search for [ by a search for tr, a program we care more,
  as [ is the builtin test anyway,
- fix a typo in the name of the GNU tools collection searched for.

Change-Id: Id78737eba10e96c6fa41ca68a47102ab28e6031f
PiperOrigin-RevId: 166685117

compile.sh

@@ -36,8 +36,8 @@ esac
 
 # Check that the bintools can be found, otherwise we would see very confusing
 # error messages.
-which [ >&/dev/null || {
-  echo >&2 "ERROR: cannot locate GNU bintools; check your PATH."
+hash tr >&/dev/null || {
+  echo >&2 "ERROR: cannot locate GNU coreutils; check your PATH."
   echo >&2 "       (You may need to run 'export PATH=/bin:/usr/bin:\$PATH)'"
   exit 1
 }

src/test/docker/Dockerfile.centos6.7

@@ -3,7 +3,7 @@ FROM centos:centos6.7
 RUN yum -y upgrade
 
 RUN yum -y install \
-    wget which git findutils binutils \
+    wget git findutils binutils \
     zip unzip tar gzip zlib-devel \
     clang gcc gcc-c++ \
     java java-devel java-1.8.0-openjdk-devel \

src/test/docker/Dockerfile.fedora23

@@ -2,7 +2,7 @@ FROM fedora:23
 
 RUN dnf -y update && dnf clean all
 RUN dnf -y install \
-    which findutils binutils gcc tar git \
+    findutils binutils gcc tar git \
     gzip zip unzip zlib-devel \
     clang java java-devel python \
     && dnf clean all