Bug 818218 - pre: Add RepositorySessionBundle tests.
Bug 818218 - pre: Make RepositorySessionBundle compose rather than inherit ExtendedJSONObject.
Bug 818218 - pre: Remove unused JPAKE cruft.
Bug 818218 - pre: Use JSONParser directly in JPAKE GetChannelStage.
Bug 818218 - Add ExtendedJSONObject.parseJSONArray static method, use it, and reduce direct access to JSONParser.
Bug 818218 - Move CryptoRecord.parseUTF8AsJSONObject to ExtendedJSONObject.

This is in preparation for sharing JSONParser instances.
Bug 818218 - Test some ExtendedJSONObject functions.
Bug 818218 - Remove ExtendedJSONObject.getJSONObject.

This avoids the confusing getObject/getJSONObject choice and will
funnel future developers towards the far more common choice.
Bug 818218 - Remove SyncResponse.jsonBody().
Bug 818218 - Remove unused method ExtendedJSONObject.clone.
Bug 818218 - Add ExtendedJSONObject.getJSONParser.

This level of indirection will be the wedge for optimizing JSONParser
instance creation.
Bug 818218 - post: Fold TestJSONParsing.java into TestExtendedJSONObject.java.
Bug 818218 - Refactor ExtendendJSONObject parsing. r=rnewman