From d0b9edcb9c5a055d344ccc1e1c2fb94563bf6413 Mon Sep 17 00:00:00 2001
From: wolfbeast <mcwerewolf@gmail.com>
Date: Fri, 10 Jun 2016 21:43:49 +0200
Subject: [PATCH] Add media.default_volume preference

---
 dom/html/HTMLMediaElement.cpp | 8 ++++++++
 modules/libpref/init/all.js   | 3 +++
 2 files changed, 11 insertions(+)

diff --git a/dom/html/HTMLMediaElement.cpp b/dom/html/HTMLMediaElement.cpp
index 89801da64f..9979922001 100644
--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -2098,7 +2098,15 @@ HTMLMediaElement::HTMLMediaElement(already_AddRefed<mozilla::dom::NodeInfo>& aNo
     gMediaElementEventsLog = PR_NewLogModule("nsMediaElementEvents");
   }
 #endif
+  ErrorResult rv;
 
+  double defaultVolume = Preferences::GetFloat("media.default_volume", 1.0);
+  if (defaultVolume < 0.0 || defaultVolume > 1.0) {
+    // Invalid, set to default 1.0
+    defaultVolume = 1.0;
+  }
+  SetVolume(defaultVolume, rv);
+  
   mAudioChannel = AudioChannelService::GetDefaultAudioChannel();
 
   mPaused.SetOuter(this);
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index cdfd729084..ff5878d237 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -262,6 +262,9 @@ pref("media.cache_readahead_limit", 999999);
 // Master HTML5 media volume scale.
 pref("media.volume_scale", "1.0");
 
+// Default media volume
+pref("media.default_volume", "1.0");
+
 // Timeout for wakelock release
 pref("media.wakelock_timeout", 2000);