Add UMA for testing whether device supports memory mapping APK files with executable permissions.

base/android/library_loader/library_loader_hooks.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/android/library_loader/library_loader_hooks.h"
 
 #include "base/android/command_line_android.h"
 #include "base/android/jni_string.h"
 #include "base/at_exit.h"
 #include "base/metrics/histogram.h"
@@ skipping 13 matching lines @@
 void SetLibraryLoadedHook(LibraryLoadedHook* func) {
   g_registration_callback = func;
 }
 
 static void InitCommandLine(JNIEnv* env, jclass clazz,
                             jobjectArray init_command_line) {
   InitNativeCommandLineFromJavaArray(env, init_command_line);
 }
 
 static jboolean LibraryLoaded(JNIEnv* env, jclass clazz) {
-  if(g_registration_callback == NULL) {
+  if (g_registration_callback == NULL) {
     return true;
   }
   return g_registration_callback(env, clazz);
 }
 
 static void RecordChromiumAndroidLinkerHistogram(
     JNIEnv* env,
     jclass clazz,
     jboolean loaded_at_fixed_address_failed,
     jboolean is_low_memory_device) {
   UMA_HISTOGRAM_BOOLEAN("ChromiumAndroidLinker.LoadedAtFixedAddressFailed",
                         loaded_at_fixed_address_failed);
   UMA_HISTOGRAM_BOOLEAN("ChromiumAndroidLinker.IsLowMemoryDevice",
                         is_low_memory_device);
 }
 
+static void RecordChromiumAndroidLinkerLoadFromApkSucceededHistogram(
+    JNIEnv* env,

[picksi1, 2014/10/10 10:52:17]

Is this the naming convention? If so fine, otherwise it might be more readable
as RecordHistogramForChromiumAndroidLinkerLoadFromAPKSucceeded? Although a
shorter name wouldn't hurt!

[petrcermak, 2014/10/10 14:20:14]

I moved the code to the existing RecordChromiumAndroidLinkerBrowserHistogram
method.

+    jclass clazz,
+    jboolean success) {
+  UMA_HISTOGRAM_BOOLEAN("ChromiumAndroidLinker.LoadFromApkSucceeded",
+                        success);
+}
+
 void LibraryLoaderExitHook() {
   if (g_at_exit_manager) {
     delete g_at_exit_manager;
     g_at_exit_manager = NULL;
   }
 }
 
 bool RegisterLibraryLoaderEntryHook(JNIEnv* env) {
   // We need the AtExitManager to be created at the very beginning.
   g_at_exit_manager = new base::AtExitManager();
 
   return RegisterNativesImpl(env);
 }
 
 void SetVersionNumber(const char* version_number) {
   g_library_version_number = strdup(version_number);
 }
 
 jstring GetVersionNumber(JNIEnv* env, jclass clazz) {
   return ConvertUTF8ToJavaString(env, g_library_version_number).Release();
 }
 
 static void RecordNativeLibraryHack(JNIEnv*, jclass, jboolean usedHack) {
   UMA_HISTOGRAM_BOOLEAN("LibraryLoader.NativeLibraryHack", usedHack);
 }
 
 }  // namespace android
 }  // namespace base