Only force preload=none over cellular for http, https, ftp URLs.

third_party/WebKit/Source/core/html/HTMLMediaElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
index 9cf088ea4a43868bb36da0181b2db08f23d4ea81..b06999fc8fef9ecf7be5adac38493fe5c88b2d5a 100644
--- a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
@@ -1008,6 +1008,9 @@ void HTMLMediaElement::loadResource(const KURL& url, ContentType& contentType)
         if (effectivePreloadType() == WebMediaPlayer::PreloadNone) {
             WTF_LOG(Media, "HTMLMediaElement::loadResource(%p) : Delaying load because preload == 'none'", this);
             deferLoad();
+        } else if (networkStateNotifier().isCellularConnectionType() && (m_currentSrc.protocolIsInHTTPFamily() || m_currentSrc.protocolIs("ftp"))) {

[philipj_slow, 2016/03/21 11:59:37]

OK, so since we last discussed this, srirama@ has done some refactoring so that
effectivePreloadType() is now the single source of truth for preload. So you
should be able to simply move these bits into effectivePreloadType(), which
would also make it very clear how it interacts with autoplay and the
m_ignorePreloadNone state. (I assume that preload should not matter, but that
m_ignorePreloadNone should take precedent, so some reshuffling will be needed.)

If the log message is important, maybe effectivePreloadType() could take an
extra out argument to say why preload was none. Seems like overkill, though.

+            WTF_LOG(Media, "HTMLMediaElement::loadResource(%p) : Delaying load because because of cellular network.", this);
+            deferLoad();
         } else {
             startPlayerLoad();
         }
@@ -1923,12 +1926,6 @@ void HTMLMediaElement::setPreload(const AtomicString& preload)
 
 WebMediaPlayer::Preload HTMLMediaElement::preloadType() const
 {
-    // Force preload to none for cellular connections.
-    if (networkStateNotifier().isCellularConnectionType()) {
-        UseCounter::count(document(), UseCounter::HTMLMediaElementPreloadForcedNone);
-        return WebMediaPlayer::PreloadNone;
-    }
-
     const AtomicString& preload = fastGetAttribute(preloadAttr);
     if (equalIgnoringCase(preload, "none")) {
         UseCounter::count(document(), UseCounter::HTMLMediaElementPreloadNone);