MultiFileMetadataSourceImpl.

The preprocessor expression defined(COMPILER_GCC) is used in code copied
from the Chromium project, but COMPILER_GCC is not defined by GCC itself,
but by the following expression in Chromium's build_config.h:

#if defined(__GNUC__)
#define COMPILER_GCC 1
#elif // ...

It must therefore be changed when copying the code out of the Chromium
code base.

This is a cherry-pick from the Chromium project, from where this
implementation of basictypes.h once originated:

https://chromium.googlesource.com/chromium/src/+/539fc83

- Adds the manifest entries to the basic tools JAR.

- Creates a symlink named like the dependencies JAR that was used
  previously.

- Creates a symlink to the protobuf JAR.

In the manifest, the classpath reference to the protobuf JAR is a
relative filename. The second symbolic link satisfies that by linking to
the installed JAR.

This is only needed for people building packages

People who build normally with Maven will find that "mvn package" still
produces the original tools JAR which has its own Main-Class attribute

Author: daniel@pocock.pro

Normally it is not a good idea to place <version> constraints in the
definition of plugins in pom.xml unless a specific version really is
needed.

This patch removes the constraints.

There are various benefits to this, one of them is that it will always
build with the latest packaged version of the plugins on a Debian or
Ubuntu system.

Author: daniel@pocock.pro

R=jia.shao.peng@gmail.com
BUG=

Review URL: https://codereview.appspot.com/122480043

No change in functionality.

This is done by adding a USE_BOOST compile time flag that is enabled by default
when the library is compiled with CMake (mainly for external users).

In Chromium, the library will be built without the USE_BOOST compile time flag.
Instead the NO_THREAD_SAFETY flag will have to be provided so that the minimal
non-thread-safe subset of base will be used.
This is possible since libphonenumber is only used from the UI thread in
Chromium.

BUG=http://crbug.com/236272
R=jia.shao.peng@gmail.com

Review URL: https://codereview.appspot.com/8859052

This will be needed to make libphonenumber depend on its own base/ rather than
Chromium's one as it is the case currently.

BUG=http://crbug.com/236272
R=jia.shao.peng@gmail.com

Review URL: https://codereview.appspot.com/8797048

library but be able to build the library from source as current practice is.
Review URL: https://codereview.appspot.com/6602047

Review URL: https://codereview.appspot.com/6350083

Review URL: https://codereview.appspot.com/6353060

- Make command line parameters named instead of positional.

- Move all information about paths, names, etc., from being hardcoded into the
  tool itself to command line parameters, so that new files in the future can
  be generated by just adding build rules for them without having to update the
  tool.

- Not hard-code class or package names, but get them from the Class object.

- Break code generation up into smaller parts, to make it easier to extend the
  code generation and share code while generating different classes.

- Update BuildMetadataFromXml to not output empty region codes.

- Generate either a Map or a Set, depending on whether the mapping table
  actually contains any data or not.

All files generated by the tool remain identical to before this change.
Review URL: https://codereview.appspot.com/6343066

Review URL: https://codereview.appspot.com/6351054

Review URL: https://codereview.appspot.com/6355051

This was also causing a compilation error with GCC 4.8.

This CL also removes basictypes.h.orig accidentally added in the previous
revision.

Review URL: http://codereview.appspot.com/5574080

Review URL: http://codereview.appspot.com/5532089