Update the HTML Media Capture implementation.

ui/shell_dialogs/select_file_dialog_android.cc

Index: ui/shell_dialogs/select_file_dialog_android.cc
diff --git a/ui/shell_dialogs/select_file_dialog_android.cc b/ui/shell_dialogs/select_file_dialog_android.cc
index b4dc7e8dc6945c931bc86367635b7e605349111e..e4d284f52a1a9da03160c3ba7b0d37662ab08dfb 100644
--- a/ui/shell_dialogs/select_file_dialog_android.cc
+++ b/ui/shell_dialogs/select_file_dialog_android.cc
@@ -63,23 +63,50 @@ void SelectFileDialogImpl::SelectFileImpl(
   JNIEnv* env = base::android::AttachCurrentThread();
 
   ScopedJavaLocalRef<jstring> capture_value;
-  std::vector<base::string16> accept_types;
-  if (params) {
-    accept_types = *(reinterpret_cast<std::vector<base::string16>*>(params));
 
-    // The last string in params is expected to be the string
-    // with capture value.
-    capture_value = base::android::ConvertUTF16ToJavaString(env,
-          StringToLowerASCII(accept_types.back()));
+  // The first element in the pair is a list of accepted types, the second
+  // indicates whether the device's capture capabilities should be used.
+  typedef std::pair<std::vector<base::string16>, bool> AcceptTypes;
+  AcceptTypes accept_types;
+
+  if (params) {
+    accept_types = *(reinterpret_cast<AcceptTypes*>(params));
+
+    // The latest version of the HTML Media Capture spec says the "capture"

[joth, 2013/07/03 17:41:42]

nit: 'latest' is ambiguous when read in future. Include a date, or say "As of
spec version x.y..."

+    // attribute should be a boolean, and implementations are supposed to infer
+    // which application to launch based on the value of the "accept"
+    // attribute. However, since we have already shipped an implementation of

[joth, 2013/07/03 17:41:42]

likewise, could say versions of chrome up to M29 shipped with....

+    // an earlier version of the spec in which the "capture" attribute was an
+    // enum, we need to keep compatibility for a while. We do that by creating
+    // a valid string value accepted by SelectFileDialog.java based on the
+    // contents of the "accept" attribute. This approximation is not 100%
+    // compatible with the previous behavior, as we cannot infer a value for
+    // "capture" if "accept" is set to something like "*/*" or
+    // "audio/*,video/*".
+    // TODO: crbug.com/240252 We need to phase out support for the old version
+    // of the spec at some point.

[joth, 2013/07/03 17:41:42]

I'm still feeling mislead by this comment. An old website that says
"capture=camera" will have the 'camera' value ignored, regardless of the block
of code here.
I think that's acceptable. But I just think we need to update the comment to not
suggest this if/else ladder is trying to retain site backwards compat. I think
it's really just retaining Java SelectFileDialog backwards compat. (And we can
remove that... see next comment)

+    bool has_capture_attribute = accept_types.second;
+    string16 normalized_capture_value;
+
+    if (has_capture_attribute && accept_types.first.size() == 1) {
+      if (StartsWithASCII(accept_types.front(), "image/*", false)) {
+        normalized_capture_value = "camera";
+      } else if (StartsWithASCII(accept_types.front(), "video/*", false)) {
+        normalized_capture_value = "camcorder";
+      } else if (StartsWithASCII(accept_types.front(), "audio/*", false)) {
+        normalized_capture_value = "microphone";
+      }
+    }
+
+    capture_value = base::android::ConvertUTF16ToJavaString(
+        env, normalized_capture_value);
     base::android::CheckException(env);
-    accept_types.pop_back();
   } else {
     capture_value = base::android::ConvertUTF8ToJavaString(env, "filesystem");
   }
 
-  // The rest params elements are expected to be accept_types.
   ScopedJavaLocalRef<jobjectArray> accept_types_java =
-      base::android::ToJavaArrayOfStrings(env, accept_types);
+      base::android::ToJavaArrayOfStrings(env, accept_types.first);
 
   Java_SelectFileDialog_selectFile(env, java_object_.obj(),
                                    accept_types_java.obj(),