[SPARK-6293] SQLContext.implicits should provide automatic conversion for RDD[Row]

[kaka1992]

Add RDD[Row] implicits change to DataFrame and unit test in DataFrameImplicitsSuite test("RDD[Row]").

[yhuai]

@kaka1992 Most of the time, the schema of a row will be null (actually, only a GenericRowWithSchema has a schema). So, I think we cannot add this implicit method.

[marmbrus]

ok to test

[marmbrus]

I think I agree with @yhuai. I'm not sure if that test cases is even making the implicit fire.

[marmbrus]

As such I would suggest we close this issue.

[kaka1992]

Maybe we can rebuild the schema using the exist row when the it doesn't contain schema data.

[SparkQA]

Test build #28759 has finished for PR 5040 at commit eddd634.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[kaka1992]

I add some code to fix char support in dataTypes when we want to get char schema info.
[SPARK-6412]

[SparkQA]

Test build #28873 has finished for PR 5040 at commit 73d7773.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #28874 has finished for PR 5040 at commit a2eaf3d.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.