Respect kLogJsConsoleMessages on all platforms

kLogJsConsoleMessages feature is used to control whether to log JS
console messages, which provides developers a quick way to control
whether to log JS messages. For example, some JS code uses a lot of log
messages which can be noisy.

Currently this feature only take effect on Android where it's disabled
by default. This CL change the logic to check this feature on all
platforms. On non-Android platforms the feature is enabled by default,
which matches the existing behavior.

To disable JS console messages in terminal, use
  --disable-features=LogJsConsoleMessages

Change-Id: I0f42e71d63f55369d1d6721c2a1c5eb3b3ef4bda
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2208352Reviewed-by: Hazem Ashmawy <hazems@chromium.org>
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Xiaohan Wang <xhwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#771261}

content/browser/log_console_message.cc

@@ -52,10 +52,8 @@ void LogConsoleMessage(blink::mojom::ConsoleMessageLevel log_level,
   if (is_off_the_record && !is_builtin_component)
     return;
 
-#if defined(OS_ANDROID)
   if (!base::FeatureList::IsEnabled(features::kLogJsConsoleMessages))
     return;
-#endif  // OS_ANDROID
 
   logging::LogMessage("CONSOLE", line_number, resolved_level).stream()
       << "\"" << message << "\", source: " << source_id << " (" << line_number

content/public/common/content_features.cc

@@ -324,8 +324,14 @@ const base::Feature kLazyInitializeMediaControls{
 const base::Feature kLegacyWindowsDWriteFontFallback{
     "LegacyWindowsDWriteFontFallback", base::FEATURE_DISABLED_BY_DEFAULT};
 
-const base::Feature kLogJsConsoleMessages{"LogJsConsoleMessages",
-                                          base::FEATURE_DISABLED_BY_DEFAULT};
+const base::Feature kLogJsConsoleMessages {
+  "LogJsConsoleMessages",
+#if defined(OS_ANDROID)
+      base::FEATURE_DISABLED_BY_DEFAULT
+#else
+      base::FEATURE_ENABLED_BY_DEFAULT
+#endif
+};
 
 // Enables lowering the priority of the resources in iframes.
 const base::Feature kLowPriorityIframes{"LowPriorityIframes",