Add the Errorprone Java Compiler

These changes let the errorprone compiler find problems when building Android.
A global flag disabled Errorprone by default.

When enabled, code problems will be shown with suggestions on how to fix them.

BUG=485599

Review URL: https://codereview.chromium.org/1136573002

Cr-Commit-Position: refs/heads/master@{#335509}

1 files changed, 21 insertions, 6 deletions

diff --git a/build/host_jar.gypi b/build/host_jar.gypi
index 9c35177..a47f6bb 100644
--- a/build/host_jar.gypi
+++ b/build/host_jar.gypi
@@ -53,6 +53,8 @@
     'jar_path': '<(jar_dir)/<(jar_name)',
     'main_class%': '',
     'stamp': '<(intermediate_dir)/jar.stamp',
+    'enable_errorprone%': '0',
+    'errorprone_exe_path': '<(PRODUCT_DIR)/bin.java/chromium_errorprone',
   },
   'all_dependent_settings': {
     'variables': {
@@ -64,18 +66,25 @@
       'action_name': 'javac_<(_target_name)',
       'message': 'Compiling <(_target_name) java sources',
       'variables': {
-        'extra_options': [],
+        'extra_args': [],
+        'extra_inputs': [],
         'java_sources': [ '<!@(find <@(src_paths) -name "*.java")' ],
         'conditions': [
           ['"<(excluded_src_paths)" != ""', {
             'java_sources!': ['<!@(find <@(excluded_src_paths) -name "*.java")']
           }],
           ['"<(jar_excluded_classes)" != ""', {
-            'extra_options': ['--jar-excluded-classes=<(jar_excluded_classes)']
+            'extra_args': ['--jar-excluded-classes=<(jar_excluded_classes)']
           }],
           ['main_class != ""', {
-            'extra_options': ['--main-class=>(main_class)']
-          }]
+            'extra_args': ['--main-class=>(main_class)']
+          }],
+          ['enable_errorprone == 1', {
+            'extra_inputs': [
+              '<(errorprone_exe_path)',
+            ],
+            'extra_args': [ '--use-errorprone-path=<(errorprone_exe_path)' ],
+          }],
         ],
       },
       'inputs': [
@@ -83,6 +92,7 @@
         '<(DEPTH)/build/android/gyp/javac.py',
         '^@(java_sources)',
         '>@(input_jars_paths)',
+        '<@(extra_inputs)',
       ],
       'outputs': [
         '<(jar_path)',
@@ -95,7 +105,7 @@
         '--chromium-code=<(chromium_code)',
         '--stamp=<(stamp)',
         '--jar-path=<(jar_path)',
-        '<@(extra_options)',
+        '<@(extra_args)',
         '^@(java_sources)',
       ],
     },
@@ -125,7 +135,12 @@
           ]
         }
       ]
-    }]
+    }],
+    ['enable_errorprone == 1', {
+      'dependencies': [
+        '<(DEPTH)/third_party/errorprone/errorprone.gyp:chromium_errorprone',
+      ],
+    }],
   ]
 }