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 5d26fc4d44528fa315ed60b8bec381de76469b33..f070cbd161c97fdb2345062b447ce746d079d089 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -1342,17 +1342,18 @@
             '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',