Fix javac8 compilation failure.

java 8 adds new methods to the javax.lang.model API to deal with type parameters, so add these methods without override annotations (which is a warning under Java8, but where those methods don't exist, is simply unused code..

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=61983132
Clean up Memoizer:
- Update docs
- Use HashMap instead of LinkedHashMap - we don't want the extra filed overhead in the Entry instances.
- Fix some weird visibilities
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=62153023
[Dagger 2.0] Add a simple scaffolding for proccessing @Inject in Dagger 2.  Currently, this only handles detecting erroneous usages of @Inject.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=62230490
Fix javac8 compilation failure by handling the newer wildcard visitor with an un-override-marked method.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=62378791
Fix NPE when processor runs on a provider containing a syntax error.  This will ultimately be handled by an AST scanner in advance, but for now, test for null.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=62863696
Fix NPE in Dagger. This one derives from a bad upstream compilation state from a missing import of @Provides.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=63135616
[Dagger 2.0] Add errors for invalid qualifiers and scopes.  Also, upgrade the error reporting infrastructure a bit.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=63162523
[Dagger 2.0] Add a utility method for collecting the TypeElements referenced from a TypeMirror.  This will be used to collect types to be imported in generated source files.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=63164643