GN(android): Filter R.class files before obfuscating via proguard

I haven't heard of this causing issues for us yet, but I realized that
filtering after proguarding could have the result that proguard renames
a class to "R.class", and then filtering strips it out.

BUG=585576

Review-Url: https://codereview.chromium.org/1993893002
Cr-Original-Commit-Position: refs/heads/master@{#394638}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 2142bcde69837585c1571a46cf59715a81d573f9

config/android/internal_rules.gni

@@ -603,22 +603,30 @@ template("process_java_prebuilt") {
   if (defined(invoker.jar_excluded_patterns)) {
     _jar_excluded_patterns = invoker.jar_excluded_patterns
   }
-
   _strip_resource_classes =
       defined(invoker.strip_resource_classes) && invoker.strip_resource_classes
+  _filter_jar = _jar_excluded_patterns != [] || _strip_resource_classes
 
-  if (_jar_excluded_patterns != [] || _strip_resource_classes) {
-    _filter_class_files_input_file = _input_jar_path
-    if (_proguard_preprocess) {
-      _filter_class_files_input_file =
-          "$target_out_dir/$target_name-proguarded.jar"
-    }
+  if (_filter_jar) {
+    _filter_target = "${target_name}__filter"
+    _output_jar_target = _filter_target
+  }
+  if (_proguard_preprocess) {
+    _proguard_target = "${target_name}__proguard_process"
+    _output_jar_target = _proguard_target
+  }
+  if (!_filter_jar && !_proguard_preprocess) {
+    _copy_target = "${target_name}__copy"
+    _output_jar_target = _copy_target
   }
 
-  if (_proguard_preprocess) {
-    _proguard_config_path = invoker.proguard_config
-    _proguard_target = "${target_name}__proguard_process"
-    proguard(_proguard_target) {
+  if (_filter_jar) {
+    _filtered_jar_path = _output_jar_path
+    if (_proguard_preprocess) {
+      _filtered_jar_path = "$target_out_dir/$target_name-filtered.jar"
+    }
+    action(_filter_target) {
+      script = "//build/android/gyp/jar.py"
       forward_variables_from(invoker,
                              [
                                "deps",
@@ -627,12 +635,47 @@ template("process_java_prebuilt") {
       inputs = [
         _build_config,
         _input_jar_path,
+      ]
+      outputs = [
+        _filtered_jar_path,
+      ]
+      args = [
+        "--input-jar",
+        rebase_path(_input_jar_path, root_build_dir),
+        "--jar-path",
+        rebase_path(_filtered_jar_path, root_build_dir),
+        "--excluded-classes=$_jar_excluded_patterns",
+      ]
+      if (_strip_resource_classes) {
+        args += [ "--strip-resource-classes-for=@FileArg($_rebased_build_config:javac:resource_packages)" ]
+      }
+    }
+  }
+
+  if (_proguard_preprocess) {
+    _proguard_config_path = invoker.proguard_config
+    proguard(_proguard_target) {
+      if (_filter_jar) {
+        _proguard_input_jar = _filtered_jar_path
+        public_deps = [
+          ":$_filter_target",
+        ]
+      } else {
+        _proguard_input_jar = _input_jar_path
+        public_deps = []
+      }
+      if (defined(invoker.deps)) {
+        deps = invoker.deps
+      }
+      if (defined(invoker.public_deps)) {
+        public_deps += invoker.public_deps
+      }
+      inputs = [
+        _build_config,
         _proguard_config_path,
+        _proguard_input_jar,
       ]
       output_jar_path = _output_jar_path
-      if (defined(_filter_class_files_input_file)) {
-        output_jar_path = _filter_class_files_input_file
-      }
 
       _rebased_input_paths = [ rebase_path(_input_jar_path, root_build_dir) ]
       _rebased_proguard_configs =
@@ -643,9 +686,8 @@ template("process_java_prebuilt") {
         "--classpath=@FileArg($_rebased_build_config:javac:classpath)",
       ]
     }
-  } else if (_jar_excluded_patterns == [] && !_strip_resource_classes) {
-    _output_jar_target = "${target_name}__copy_jar"
-    copy(_output_jar_target) {
+  } else if (!_filter_jar) {
+    copy(_copy_target) {
       forward_variables_from(invoker,
                              [
                                "deps",
@@ -660,42 +702,6 @@ template("process_java_prebuilt") {
     }
   }
 
-  if (_jar_excluded_patterns != [] || _strip_resource_classes) {
-    _output_jar_target = "${target_name}__filter"
-    action(_output_jar_target) {
-      script = "//build/android/gyp/jar.py"
-      if (_proguard_preprocess) {
-        deps = [
-          ":$_proguard_target",
-        ]
-      } else {
-        forward_variables_from(invoker,
-                               [
-                                 "deps",
-                                 "public_deps",
-                               ])
-      }
-      inputs = [
-        _filter_class_files_input_file,
-      ]
-      outputs = [
-        _output_jar_path,
-      ]
-      args = [
-        "--input-jar",
-        rebase_path(_filter_class_files_input_file, root_build_dir),
-        "--jar-path",
-        rebase_path(_output_jar_path, root_build_dir),
-        "--excluded-classes=$_jar_excluded_patterns",
-      ]
-      if (_strip_resource_classes) {
-        args += [ "--strip-resource-classes-for=@FileArg($_rebased_build_config:javac:resource_packages)" ]
-      }
-    }
-  } else if (_proguard_preprocess) {
-    _output_jar_target = _proguard_target
-  }
-
   group(target_name) {
     forward_variables_from(invoker,
                            [
@@ -1615,6 +1621,9 @@ template("compile_java") {
     deps = [
       ":$_javac_target_name",
     ]
+    if (defined(invoker.deps)) {
+      deps += invoker.deps
+    }
   }
 
   emma_instr(_emma_instr_target_name) {