Move classes.jar generation right below JarJar phase.

By doing this, we don't need run desugar/Jacoco/proguard twice for
static java libraries(one for their self build, another for downstream
dependents).

Test: m clean && m java
Bug: b/65455145
Change-Id: I87aee34940937dbde33a977f55d1faf2c8054561
3 files changed