android envsetup: Remove default_target=All

If targets shouldn't be part of the android build, they should be conditional
in gyp instead.

Removing this line leads to 17 more files being compiled and one more binary
(printing_unittests) being linked on the open source bots, and there are no
build errors.

(An internal build of the 'all' target is also successful, and it builds only
183 additional edges too, which add about 1 minute / 5% to build time.)

BUG=330631
NOTRY=true

Review URL: https://codereview.chromium.org/149103002

git-svn-id: http://src.chromium.org/svn/trunk/src/build@247571 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

android/envsetup_functions.sh

@@ -128,9 +128,6 @@ ${ANDROID_SDK_BUILD_TOOLS_VERSION}
 common_gyp_vars() {
   export GYP_DEFINES="${DEFINES}"
 
-  # Use our All target as the default
-  export GYP_GENERATOR_FLAGS="${GYP_GENERATOR_FLAGS} default_target=All"
-
   # TODO(thakis): Remove this after a week or two. Sourcing envsetup.sh used to
   # set this variable, but now that all_android.gyp is gone having it set will
   # lead to errors, so explicitly unset it to remove it from the environment of