Bug 1405396 - Pre: Set file.encoding=utf-8 for GeckoView packaging. r=maliu

We already had a work-around in place for Gradle invocations, but
apparently that wasn't enough for the Maven deployer, which must
launch its own JVM, which doesn't have the correct file encoding on
Linux.

MozReview-Commit-ID: 4z1IEZBmLaz

--HG--
extra : rebase_source : 951bb4c75ecba0d83cb86e728e1164dda99a6a08
extra : source : 6dd2abe095b82ed1a0fed4e687a7bbf3a5e036de

mobile/android/mach_commands.py

@@ -316,10 +316,20 @@ class MachCommands(MachCommandBase):
         # Android tools expect UTF-8: see
         # http://tools.android.com/knownissues/encoding.  See
         # http://stackoverflow.com/a/21267635 for discussion of this approach.
+        #
+        # It's not even enough to set the encoding just for Gradle; it
+        # needs to be for JVMs spawned by Gradle as well.  This
+        # happens during the maven deployment generating the GeckoView
+        # documents; this works around "error: unmappable character
+        # for encoding ASCII" in exoplayer2.  See
+        # https://discuss.gradle.org/t/unmappable-character-for-encoding-ascii-when-building-a-utf-8-project/10692/11
+        # and especially https://stackoverflow.com/a/21755671.
+
         return self.run_process([self.substs['GRADLE']] + gradle_flags + ['--console=plain'] + args,
             append_env={
                 'GRADLE_OPTS': '-Dfile.encoding=utf-8',
                 'JAVA_HOME': java_home,
+                'JAVA_TOOL_OPTIONS': '-Dfile.encoding=utf-8',
             },
             pass_thru=True, # Allow user to run gradle interactively.
             ensure_exit_code=False, # Don't throw on non-zero exit code.