[Android WebView] Implement WebSettings.{get|set}CacheMode

android_webview/browser/aw_contents_io_thread_client.h

Index: android_webview/browser/aw_contents_io_thread_client.h
diff --git a/android_webview/browser/aw_contents_io_thread_client.h b/android_webview/browser/aw_contents_io_thread_client.h
index 0dd414623db006fad9cc079441187f97612fc37a..fad8a1ac78a481db35acec13a0e7eb0e191ece69 100644
--- a/android_webview/browser/aw_contents_io_thread_client.h
+++ b/android_webview/browser/aw_contents_io_thread_client.h
@@ -34,8 +34,21 @@ class InterceptedRequestData;
 // don't keep a AwContentsIoThreadClient if you don't need to.
 class AwContentsIoThreadClient {
  public:
+  // Corresponds to WebSettings cache mode constants.
+  enum CacheMode {
+    LOAD_DEFAULT = -1,
+    LOAD_NORMAL = 0,
+    LOAD_CACHE_ELSE_NETWORK = 1,
+    LOAD_NO_CACHE = 2,
+    LOAD_CACHE_ONLY = 3,
+  };
+
   virtual ~AwContentsIoThreadClient() {}
 
+  // Retrieve CacheMode setting value of this AwContents.
+  // This method is called on the IO thread only.
+  virtual CacheMode GetCacheMode() const = 0;
+
   // This will attempt to fetch the AwContentsIoThreadClient for the given
   // |render_process_id|, |render_view_id| pair.
   // This method can be called from any thread.