Fix a couple of typos in the Compile Testing package javadoc, and add a link to show what the unqualified method javaSource() that appears there actually is.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65406423
Fix bug where only ClassTrees with kind CLASS are considered by TypeScanner, resulting in a broken generatesSources() for interfaces, enums, and annotation types.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65448993
Minor cleanups for the c.g.testing.compile javadocs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65461195
Created DetailedEqualityScanner for providing more in-depth error reporting inside Compile Testing's generatesSources()
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66117067
Fix NPE thrown on FileClauses when there are Diagnostics that aren't associated with any element.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66118534
Rename left/right/base/reference to a consistent expected/actual so that reading, labeling, and testing TreeDiffer doesn't require mental gymnastics.

Also reverse order of expected and actual arguments in TreeDiffer to be consistent with convention and to fix previously incorrect labeling of expected / actual tree diffs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=67161240
Fix NPE caused by bad scan() in TreeDiffer.java

Old scan() ignored the possibility of an expected node having a null value when an actual node existed. The new scan() accounts for this possibility and also throws a more relevant NPE should another similar situation arise.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68173457
Make the failsToCompile() and compilesWithoutError() clauses report the files they generate on failure.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68173836
Set build to constrain itself to Java 1.6 (and fix attendant errors)

This still leaves usage of APIs not in 1.6 classpath, but it's a start.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68833477
Remove an unused constant that is also incompatible with java6.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68834592
Change TypeEnumerator to rely on the default behavior of the TreeScanner rather than checking the kind against an EnumSet.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68838183
Fix an IAE that's thrown when attempting to contextualize empty nodes.

TreeContext formerly threw an IAE when requests for line and column information returned Diagnostic.NOPOS. No guarantee exists that valid nodes in a given CompilationUnitTree will be assigned position data other than Diagnostic.NOPOS. In practice, our implementation of SourcePosition returns this value for empty nodes (say, an empty modifier list).

This change makes it so that IAE is only thrown when no NodePath exists between a TreeContext's compilation unit and the node provided. Additionally, it modifies the getNodeStartPostion and getNodeEndPosition methods so that they climb the TreePath when looking for position data. This is so that e.g. an empty modifier list may be contextualized to its associated class.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68841400
Fix test failures that aries when running under different Java configurations.

TreeDifferTest was relying on the assumption that TreePath.getPath() would find a valid tree path from CompilationUnitTree A to subtree B if that subtree was identical to one found by a traversal of CompilationUnitTree A. This behavior is apparently not guaranteed.

JavaSourcesSubjectFactoryTest makes some assumptions about how many diagnostics will be reported before failure. This CL changes it to only look for the specific diagnostics for which it is testing.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=70104902