Remove the allow-displaying-mixed-content setting from Blink.

android_webview/native/aw_settings.cc

Index: android_webview/native/aw_settings.cc
diff --git a/android_webview/native/aw_settings.cc b/android_webview/native/aw_settings.cc
index 77892fd59a0e8101b5edeb55f59101a100af638f..88eab9eb0802505e497b3d41e4101e4cbe4c65a0 100644
--- a/android_webview/native/aw_settings.cc
+++ b/android_webview/native/aw_settings.cc
@@ -429,10 +429,21 @@ void AwSettings::PopulateWebPreferencesLocked(JNIEnv* env,
       web_prefs->experimental_webgl_enabled &&
       enable_supported_hardware_accelerated_features;
 
-  web_prefs->allow_displaying_insecure_content =
-      Java_AwSettings_getAllowDisplayingInsecureContentLocked(env, obj);
-  web_prefs->allow_running_insecure_content =
-      Java_AwSettings_getAllowRunningInsecureContentLocked(env, obj);
+  // If mixed content running is allowed than displaying must be allowed too.
+  DCHECK(!Java_AwSettings_getAllowRunningInsecureContentLocked(env, obj) ||
+         Java_AwSettings_getAllowDisplayingInsecureContentLocked(env, obj));

[Torne, 2016/08/31 12:49:59]

These two DCHECKs are identical? Also, it'd be clearer to use DCHECK_IMPLIES,
since what you have here is an implies relation.

[carlosk, 2016/09/02 23:47:42]

Indeed. But as you also realized, DCHECK_IMPLIES is sadly no more.

+  // If mixed content displaying is not allowed than running must not be allowed
+  // either.
+  DCHECK(Java_AwSettings_getAllowDisplayingInsecureContentLocked(env, obj) ||
+         !Java_AwSettings_getAllowRunningInsecureContentLocked(env, obj));
+  if (Java_AwSettings_getAllowDisplayingInsecureContentLocked(env, obj)) {

[Torne, 2016/08/31 12:49:59]

The actual Java side value stored is an enum:
WebSettings.MIXED_CONTENT_ALWAYS_ALLOW, MIXED_CONTENT_NEVER_ALLOW,
MIXED_CONTENT_COMPATIBILITY_MODE. Currently the Java code in AwContents converts
this into two bools because that's the form web_prefs used to want.

I think it would be clearer here to either:
1) Change the Java code to just return the actual enum value to native, and let
the native code map that to strict_mixed_content_checking and
allow_running_insecure_content
or 2) Change the Java code to map the enum value to those actual two bools (and
rename the functions), and have the native code continue to be trivial
assignments to web_prefs.

rather than trying to keep the JNI the same.

[carlosk, 2016/09/02 23:47:42]

Agreed. I didn't realize those getters were used only here.

As I don't see a C++ version of those enum values I'll go with 2) as the logic
will be in Java where the enum is defined.

+    web_prefs->strict_mixed_content_checking = false;
+    web_prefs->allow_running_insecure_content =
+        Java_AwSettings_getAllowRunningInsecureContentLocked(env, obj);
+  } else {
+    web_prefs->strict_mixed_content_checking = true;
+    web_prefs->allow_running_insecure_content = false;
+  }
 
   web_prefs->fullscreen_supported =
       Java_AwSettings_getFullscreenSupportedLocked(env, obj);