Add flag use_corelib_source_files to control how dart_bootstrap and gen_snapshot load core librarie…

Add flag use_corelib_source_files to control how dart_bootstrap and gen_snapshot load core libraries during the boot strap process. If this flag is true then an attempt is made to read the core library sources files and if not present fallsback to the source bits baked in the binary.

By default the flag is false.

BUG=#27860
R=rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/7d287b232bbe749e250b70d4ecdcf66c08fef0c1

[siva, 2016-11-23 17:51:52]

asiva@google.com changed reviewers:
+ rmacnak@google.com

[rmacnak, 2016-11-23 18:03:37]

lgtm

[siva, 2016-11-23 18:26:09]

Description was changed from

==========
Add flag use_corelib_source_files to control how dart_bootstrap and gen_snapshot
load core libraries during the boot strap process. If this flag is true then an
attempt is made to read the core library sources files and if not present
fallsback to the source bits baked in the binary.

By default the flag is false.

BUG=#27860
==========

to

==========
Add flag use_corelib_source_files to control how dart_bootstrap and gen_snapshot
load core libraries during the boot strap process. If this flag is true then an
attempt is made to read the core library sources files and if not present
fallsback to the source bits baked in the binary.

By default the flag is false.

BUG=#27860
R=rmacnak@google.com

Committed:
https://github.com/dart-lang/sdk/commit/7d287b232bbe749e250b70d4ecdcf66c08fef0c1
==========

[siva, 2016-11-23 18:26:10]

Committed patchset #1 (id:1) manually as
7d287b232bbe749e250b70d4ecdcf66c08fef0c1 (presubmit successful).