Add a Java API for UMA histograms.

base/base.gyp

Index: base/base.gyp
diff --git a/base/base.gyp b/base/base.gyp
index d3a55b85d091f0965fb5c78a7e79b4c1c113f4f4..487580e7a3bd7b026d5a48580eb1548394c59ce0 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -1339,17 +1339,18 @@
             'android/java/src/org/chromium/base/FieldTrialList.java',
             'android/java/src/org/chromium/base/ImportantFileWriterAndroid.java',
             'android/java/src/org/chromium/base/JNIUtils.java',
-            'android/java/src/org/chromium/base/library_loader/LibraryLoader.java',
+            'android/java/src/org/chromium/base/JavaHandlerThread.java',
             'android/java/src/org/chromium/base/LocaleUtils.java',
             'android/java/src/org/chromium/base/MemoryPressureListener.java',
-            'android/java/src/org/chromium/base/JavaHandlerThread.java',
             'android/java/src/org/chromium/base/PathService.java',
             'android/java/src/org/chromium/base/PathUtils.java',
             'android/java/src/org/chromium/base/PowerMonitor.java',
-            'android/java/src/org/chromium/base/SystemMessageHandler.java',
             'android/java/src/org/chromium/base/SysUtils.java',
+            'android/java/src/org/chromium/base/SystemMessageHandler.java',
             'android/java/src/org/chromium/base/ThreadUtils.java',
             'android/java/src/org/chromium/base/TraceEvent.java',
+            'android/java/src/org/chromium/base/library_loader/LibraryLoader.java',
+            'android/java/src/org/chromium/base/metrics/RecordHistogram.java',
           ],
           'variables': {
             'jni_gen_package': 'base',