This commit is us getting out of our own way. We were specifying
-classpath twice, once in $(JAVAC) and once in java-build.mk. Only
the latter of these is active. This a problem for ANDROID_EXTRA_JARS
-- those JARs should be on the classpath and input to $(DX) -- and
JARs that should be on the classpath but *not* input to $(DX). This
commit removes the global flags to $(JAVAC) and adds
JAVA_{BOOT}CLASSPATH_JARS. This required some hijinkery moving
wildcards to moz.build files, but everything seems to work.
As well as clarifying some parts of the build, part 2 uses this work
to modify the classpath.
There are several parts to this ticket:
1) Produce javaaddons-1.0.jar, a standalone JAR defining a (versioned)
Java interface suitable for consumption by third-party Java addon
implementations.
2) Support the new V1 interface in the JavaAddonManager.
3) Add Robocop JavascriptTests testing the JavaScript message passing
interface to and from Java.
This patch can be read as "not in tests/" and "everything in tests/".
