Fix a bug with CharStreams.copy not clearing its buffer after reading.

Guava issue 1061: http://code.google.com/p/guava-libraries/issues/detail?id=1061
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31793143
Rollback gwt.xml change.

*** Reason for rollback ***

Breaks compilation under --check_constraints=gwt, perhaps other settings?

*** Original change description ***

Make java_and_gwt_library support extra_module_contents, even though java_library doesn't :)
This lets us remove our manually maintained (and often wrong) .gwt.xml files.
Occasionally we still need an extra_module_contents file, and we should someday figure out why.
(Note: Because java_and_gwt_library has access to information that plain java_library does not, it can actually be a bit smarter about what it puts in the .gwt.xml automatically.)
The net effect on the GWT modules themselves is mostl

... description truncated by g4 rollback ...
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31797949
Add IntMath.mean and LongMath.mean. It's an efficient implementation resilient to overflow which is useful when computing midpoints.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31799895
Update the handling of gwt.xml files.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31818898
Decrease tasks again for get() basher, which currently takes 4x as long as any other cache test.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31820210
Add tests that the custom hash table implementations expand correctly.
From Louis: http://codereview.appspot.com/6351075/
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31822084
Rephrase to stop suggesting that there are only two overloads of transform().
Also, publicly release a comment in the Future.addListener Javadoc about addCallback, which was publicly released in Guava 10 (and already mentioned publicly elsewhere in the ListenableFuture doc).
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31833262
Made TypeResolver @Beta and added clearer document.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31858151
Remove unused code.
From Louis: http://codereview.appspot.com/6343051/
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31920587
Remove unused char[] instance in CharMatcher.inRange.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31924666
Updating putString(String) spec and default implementation, to avoid
forcing implementations to inefficiently deal with unpaired surrogate characters.
This is an incompatible change for inputs with such characters.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31932872
Remove public from TypeResolver in Guava.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=31969908
Remove unused methods from c/g/common/collect
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32009861
Fix comment to refer to InternetDomainName.isValid instead of deprecated isValidLenient.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32011124
HashIterator fix for LocalCache
Remove a few unused chunks of code from common.cache
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32015573
Remove unused methods in c/g/c/{hash,reflect}/...
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32056245
Fix a comment on AbstractScheduledService.Scheduler that implied that you could create subclasses of Scheduler (that are not subclasses of CustomScheduler).  This is impossible since Scheduler has a private constructor.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32059988
Add serialization tests to the Multimap test suites.
From Louis: http://codereview.appspot.com/6421047/
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32082297
Deprecate mutator methods on immutable/unmodifiable classes in common.collect.  It can't possibly be correct to invoke a method that mutates a collection on an immutable object and this will help catch those errors at compile time.  It also has the benefit that IDEs set up to filter deprecated methods from the auto-complete suggestions will filter out the unsupported methods.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32083827
Making exception more descriptive when someone tries to proxy a class
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=32142551