Add picker view for Web Share Target.

chrome/browser/ui/browser_dialogs.h

Index: chrome/browser/ui/browser_dialogs.h
diff --git a/chrome/browser/ui/browser_dialogs.h b/chrome/browser/ui/browser_dialogs.h
index 6d2df0169030a256d3899b473bd0899e5bc1b1ff..62899ef5a65f69a8f6aa7ed18aa55b0e0272f53b 100644
--- a/chrome/browser/ui/browser_dialogs.h
+++ b/chrome/browser/ui/browser_dialogs.h
@@ -152,6 +152,20 @@ void ShowBookmarkEditorViews(gfx::NativeWindow parent_window,
 
 void ShowPaymentRequestDialog(payments::PaymentRequest* request);
 
+enum class SharePickerResult {
+  CANCEL,
+  SHARE
+};
+
+// Shows the dialog to choose a share target app. |targets| is a list of app
+// titles that will be shown in a list. Calls |callback| with SHARE if an app
+// was chosen, or CANCEL if the dialog was cancelled.
+// TODO(mgiuca): Callback should provide info about the picked app.
+void ShowWebShareTargetPickerDialog(
+    gfx::NativeWindow parent_window,
+    const std::vector<base::string16>& targets,
+    const base::Callback<void(SharePickerResult)>& callback);
+
 #if defined(OS_MACOSX)
 
 // This is a class so that it can be friended from ContentSettingBubbleContents,