[SPARK-15531][DEPLOY] spark-class tries to use too much memory when running Launcher

## What changes were proposed in this pull request?

Explicitly limit launcher JVM memory to modest 128m

## How was this patch tested?

Jenkins tests.

Author: Sean Owen <sowen@cloudera.com>

Closes #13360 from srowen/SPARK-15531.

bin/spark-class

@@ -68,7 +68,7 @@ fi
 # The exit code of the launcher is appended to the output, so the parent shell removes it from the
 # command array and checks the value to see if the launcher succeeded.
 build_command() {
-  "$RUNNER" -cp "$LAUNCH_CLASSPATH" org.apache.spark.launcher.Main "$@"
+  "$RUNNER" -Xmx128m -cp "$LAUNCH_CLASSPATH" org.apache.spark.launcher.Main "$@"
   printf "%d\0" $?
 }
 

bin/spark-class2.cmd

@@ -55,7 +55,7 @@ if not "x%JAVA_HOME%"=="x" set RUNNER=%JAVA_HOME%\bin\java
 rem The launcher library prints the command to be executed in a single line suitable for being
 rem executed by the batch interpreter. So read all the output of the launcher into a variable.
 set LAUNCHER_OUTPUT=%temp%\spark-class-launcher-output-%RANDOM%.txt
-"%RUNNER%" -cp "%LAUNCH_CLASSPATH%" org.apache.spark.launcher.Main %* > %LAUNCHER_OUTPUT%
+"%RUNNER%" -Xmx128m -cp "%LAUNCH_CLASSPATH%" org.apache.spark.launcher.Main %* > %LAUNCHER_OUTPUT%
 for /f "tokens=*" %%i in (%LAUNCHER_OUTPUT%) do (
   set SPARK_CMD=%%i
 )