Minor fix to Java sandcastle job definition

Summary:
proxy config tools are not available in sandcastle environment. Hard
coding the proxy information in the job.

Test Plan: Run manually

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D56775

build_tools/rocksdb-lego-determinator

@@ -69,7 +69,8 @@ LITE="OPT=-DROCKSDB_LITE"
 TSAN="COMPILE_WITH_TSAN=1"
 UBSAN="COMPILE_WITH_UBSAN=1"
 DISABLE_JEMALLOC="DISABLE_JEMALLOC=1"
-SETUP_JDK="export JAVA_HOME=/usr/local/jdk-7u10-64/; export PATH=\$PATH:\$JAVA_HOME/bin"
+HTTP_PROXY="https_proxy=http://fwdproxy.29.prn1:8080 http_proxy=http://fwdproxy.29.prn1:8080 ftp_proxy=http://fwdproxy.29.prn1:8080"
+SETUP_JAVA_ENV="export $HTTP_PROXY; export JAVA_HOME=/usr/local/jdk-7u10-64/; export PATH=\$PATH:\$JAVA_HOME/bin"
 PARSER="'parser':'egrep \'Failure|^#|Abort|Expected|Actual|GoogleTestFailure|^==\''"
 
 ARTIFACTS=" 'artifacts': [
@@ -647,7 +648,7 @@ JAVA_BUILD_TEST_COMMANDS="[
             $CLEANUP_ENV,
             {
                 'name':'Build RocksDB for Java',
-                'shell':'$SETUP_JDK; export `fwdproxy-config --format=sh curl`; $SHM make rocksdbjava',
+                'shell':'$SETUP_JAVA_ENV; $SHM make rocksdbjava',
                 'user':'root',
                 $PARSER
             },