[HOTFIX][ZEPPELIN-1240] Part 2. Removed interpreter properties are restored

[jongyoul]

What is this PR for?

Fixing the bug that users cannot delete some interpreter settings from interpreter tab. This is second part of ZEPPELIN-1240 for branch-0.6 only

What type of PR is it?

[Bug Fix | Hot Fix]

Todos

• - Changed update to set

What is the Jira issue?

• https://issues.apache.org/jira/browse/ZEPPELIN-1240

How should this be tested?

1. Make new interpreter via interpreter tab
2. remove some properties

Screenshots (if appropriate)

Questions:

• Does the licenses files need update? No
• Is there breaking changes for older versions? No
• Does this needs documentation? No

[minahlee]

Tested and looks good to me. Merge if there is no more discussion

FYI, there are test failure in 3 build profiles, and all of them seems irrelevant to this PR. Here are the logs of test failure:

Profile#1

[ERROR] Failed to execute goal on project zeppelin-livy: Could not resolve dependencies for project org.apache.zeppelin:zeppelin-livy:jar:0.6.1-SNAPSHOT: Could not transfer artifact org.apache.httpcomponents:httpclient:jar:4.3.4 from/to central (http://repo.maven.apache.org/maven2): GET request of: org/apache/httpcomponents/httpclient/4.3.4/httpclient-4.3.4.jar from central failed: Connection reset -> [Help 1]

Profile#2

testClose(org.apache.zeppelin.python.PythonInterpreterTest)  Time elapsed: 0.517 sec  <<< FAILURE!
java.lang.AssertionError: null
    at org.junit.Assert.fail(Assert.java:86)
    at org.junit.Assert.assertTrue(Assert.java:41)
    at org.junit.Assert.assertFalse(Assert.java:64)
    at org.junit.Assert.assertFalse(Assert.java:74)
    at org.apache.zeppelin.python.PythonInterpreterTest.testClose(PythonInterpreterTest.java:170)


Results :

Failed tests: 
  PythonInterpreterTest.testClose:170 null

Tests run: 5, Failures: 1, Errors: 0, Skipped: 0

Profile#3

�[36mRun starting. Expected test count is: 18�[0m
�[32mAngularModelTest:�[0m
�[32mAngularModel�[0m
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/home/travis/build/apache/zeppelin/zeppelin-interpreter/target/zeppelin-interpreter-0.6.1-SNAPSHOT.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/travis/build/apache/zeppelin/zeppelin-interpreter/target/lib/slf4j-log4j12-1.7.10.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/travis/.m2/repository/org/slf4j/slf4j-log4j12/1.7.10/slf4j-log4j12-1.7.10.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.slf4j.impl.Log4jLoggerFactory]
�[32m- should able to create AngularObject�[0m
�[32mAngularModel�[0m
�[32m- should able to update AngularObject�[0m
�[32mAngularModel�[0m
�[32m- should able to remove AngularObject�[0m
�[32mAngularModelTest:�[0m
�[32mAngularModel�[0m
�[32m- should able to create AngularObject�[0m
�[32mAngularModel�[0m
�[32m- should able to update AngularObject�[0m
�[32mAngularModel�[0m
�[32m- should able to remove AngularObject�[0m
�[32mAngularElemTest:�[0m
�[32mAngularElem�[0m
�[31m- should provide onclick method *** FAILED ***�[0m
�[31m  The code passed to eventually never returned normally. Attempted 1 times over 160.87031 milliseconds. Last failure message: 0 was not equal to 1. (AbstractAngularElemTest.scala:72)�[0m
�[32mAngularElem�[0m
�[32m- should print angular display directive only once in a paragraph�[0m
�[32mAngularElem�[0m
�[32m- should bind angularObject to ng-model directive�[0m
�[32mAngularElem�[0m
�[32m- should able to disassociate AngularObjects�[0m
�[32mAngularElem�[0m
�[32m- should allow access to InterpreterContext inside of callback function�[0m
�[32mAngularElem�[0m
�[32m- should able to be created from implicit conversion�[0m
�[32mAngularElemTest:�[0m
�[32mAngularElem�[0m
�[32m- should provide onclick method�[0m
�[32mAngularElem�[0m
�[32m- should print angular display directive only once in a paragraph�[0m
�[32mAngularElem�[0m
�[32m- should bind angularObject to ng-model directive�[0m
�[32mAngularElem�[0m
�[32m- should able to disassociate AngularObjects�[0m
�[32mAngularElem�[0m
�[32m- should allow access to InterpreterContext inside of callback function�[0m
�[32mAngularElem�[0m
�[32m- should able to be created from implicit conversion�[0m
�[36mRun completed in 659 milliseconds.�[0m
�[36mTotal number of tests run: 18�[0m
�[36mSuites: completed 5, aborted 0�[0m
�[36mTests: succeeded 17, failed 1, canceled 0, ignored 0, pending 0�[0m
�[31m*** 1 TEST FAILED ***�[0m

[minahlee]

This is merged to branch-0.6. @jongyoul do you mind to close it?