Modify ANTLR directory mapping and include paths to fix Java Cloud Debugger open source build on GCP.
Modify ANTLR directory mapping and include paths to fix Java Cloud Debugger open source build on GCP.

This CL is required due to CL/113141916 and CL/119635309 which changed the ANTLR generated code to:
  (a) Access headers using full path w.r.t. google3/ (i.e., third_party/antlr/...)
  (b) Not use any version substring (i.e., "v2_7_2") in those #includes.

Note that, these two CLs did not touch the antlr/lib/cpp/* files, which are
still using "#include <antlr/*.hpp>".

This CL:
 1. Adds compilation root directory as an include path (i.e., ~/cdbg/) to allow
 full-path includes.
 2. Removes "v2_7_2" substring from the MOE mappings to correctly match full include
 paths.
 3. Does not remove -I$(ANTLR_CPP_LIB_INCLUDE) to make sure the #includes under lib/cpp/*hpp still work.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=121025051

GoogleCloudPlatform/cloud-debug-java,GoogleCloudPlatform/cloud-debug-java,GoogleCloudPlatform/cloud-debug-java,GoogleCloudPlatform/cloud-debug-java