Remove hidden elements from MHTML

third_party/WebKit/Source/web/tests/WebFrameSerializerTest.cpp

Index: third_party/WebKit/Source/web/tests/WebFrameSerializerTest.cpp
diff --git a/third_party/WebKit/Source/web/tests/WebFrameSerializerTest.cpp b/third_party/WebKit/Source/web/tests/WebFrameSerializerTest.cpp
index 60d6fa6f9932a389d2fd92cf06b175414fda8fe9..70e9374e6bae9e15b9d91a74705545a3816880cb 100644
--- a/third_party/WebKit/Source/web/tests/WebFrameSerializerTest.cpp
+++ b/third_party/WebKit/Source/web/tests/WebFrameSerializerTest.cpp
@@ -215,4 +215,22 @@ TEST_F(WebFrameSerializerSanitizationTest, RemoveInlineScriptInAttributes) {
   EXPECT_NE(std::string::npos, mhtml.find("id="));
 }
 
+TEST_F(WebFrameSerializerSanitizationTest, RemoveHiddenElements) {
+  String mhtml =
+      generateMHTMLParts("http://www.test.com", "hidden_elements.html");
+
+  // These hidden elements that do not affect layout should be removed.
+  EXPECT_EQ(std::string::npos, mhtml.find("<h1"));
+  EXPECT_EQ(std::string::npos, mhtml.find("<p id=3D\"hidden_id\""));
+  EXPECT_EQ(std::string::npos, mhtml.find("<input type=3D\"hidden\""));
+
+  // These hidden elements that affect layout should remain intact.
+  EXPECT_NE(std::string::npos, mhtml.find("<h2"));
+
+  // These visible elements should remain intact.
+  EXPECT_NE(std::string::npos, mhtml.find("<h2"));
+  EXPECT_NE(std::string::npos, mhtml.find("<p id=3D\"visible_id\""));
+  EXPECT_NE(std::string::npos, mhtml.find("<input type=3D\"text\""));
+}
+
 }  // namespace blink