Move pid, stacks from envsetup.sh to dedicated scripts.

Make it so that these can be used in other scripts by moving them from
functions defined in envsetup.sh to standalone scripts.

Test: stacks zygote64
Change-Id: Id8e5ce5b4da80e57f4226eb34edaf82b87393834

envsetup.sh

@@ -974,28 +974,6 @@ function qpid() {
     fi
 }
 
-function pid()
-{
-    local prepend=''
-    local append=''
-    if [ "$1" = "--exact" ]; then
-        prepend=' '
-        append='$'
-        shift
-    fi
-    local EXE="$1"
-    if [ "$EXE" ] ; then
-        local PID=`adb shell ps \
-            | tr -d '\r' \
-            | \grep "$prepend$EXE$append" \
-            | sed -e 's/^[^ ]* *\([0-9]*\).*$/\1/'`
-        echo "$PID"
-    else
-        echo "usage: pid [--exact] <process name>"
-        return 255
-    fi
-}
-
 # coredump_setup - enable core dumps globally for any process
 #                  that has the core-file-size limit set correctly
 #
@@ -1082,37 +1060,6 @@ function systemstack()
     stacks system_server
 }
 
-function stacks()
-{
-    if [[ $1 =~ ^[0-9]+$ ]] ; then
-        local PID="$1"
-    elif [ "$1" ] ; then
-        local PIDLIST="$(pid $1)"
-        if [[ $PIDLIST =~ ^[0-9]+$ ]] ; then
-            local PID="$PIDLIST"
-        elif [ "$PIDLIST" ] ; then
-            echo "more than one process: $1"
-        else
-            echo "no such process: $1"
-        fi
-    else
-        echo "usage: stacks [pid|process name]"
-    fi
-
-    if [ "$PID" ] ; then
-        # Use `debuggerd -j` on java processes.
-        if adb shell readlink /proc/$PID/exe | egrep -q '^/system/bin/app_process' ; then
-            # But not the zygote.
-            if ! adb shell cat /proc/$PID/cmdline | egrep -q '^zygote'; then
-                adb shell debuggerd -j $PID
-                return
-            fi
-        fi
-
-        adb shell debuggerd -b $PID
-    fi
-}
-
 # Read the ELF header from /proc/$PID/exe to determine if the process is
 # 64-bit.
 function is64bit()