Add Spotless to the Gradle build

[gbrodman]

This change is 

[jianglai]

Reviewed 7 of 7 files at r1.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @gbrodman and @guyben13)

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java_common.gradle, line 56 at r1 (raw file):

../gradlew

The gradlew file is at the same level. Shouldn't it be one dot instead of two? Same below.

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java_common.gradle, line 56 at r1 (raw file):

spotlessCheck

Shouldn't we have this target be a dependent on the build task so that presubmit will prevent you from submitting malformed code?

[gbrodman]

Reviewable status: 6 of 7 files reviewed, 2 unresolved discussions (waiting on @guyben13 and @jianglai)

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java_common.gradle, line 56 at r1 (raw file):

Previously, jianglai (Lai Jiang) wrote…

../gradlew

The gradlew file is at the same level. Shouldn't it be one dot instead of two? Same below.

Done.

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java_common.gradle, line 56 at r1 (raw file):

Previously, jianglai (Lai Jiang) wrote…

spotlessCheck

Shouldn't we have this target be a dependent on the build task so that presubmit will prevent you from submitting malformed code?

The Spotless plugin actually does that by default -- if you run "./gradlew build --dry-run" you can see that :spotlessCheck shows up as one of the tasks.

[jianglai]

Reviewed 1 of 1 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @guyben13)