Remove usage of WebElement::tagName() in blink.

Source/web/tests/WebFrameTest.cpp

Index: Source/web/tests/WebFrameTest.cpp
diff --git a/Source/web/tests/WebFrameTest.cpp b/Source/web/tests/WebFrameTest.cpp
index 2ea914dcf633bdbefd3dd7fec1a736ce30f1fb0a..697707940c581f87ee7198e63b121b401b292765 100644
--- a/Source/web/tests/WebFrameTest.cpp
+++ b/Source/web/tests/WebFrameTest.cpp
@@ -3601,7 +3601,7 @@ TEST_P(ParameterizedWebFrameTest, FindInPage)
     ASSERT_FALSE(range.isNull());
     EXPECT_EQ(5, range.startOffset());
     EXPECT_EQ(9, range.endOffset());
-    EXPECT_EQ(WebString::fromUTF8("INPUT"), frame->document().focusedElement().tagName());
+    EXPECT_TRUE(frame->document().focusedElement().hasHTMLTagName("input"));
 
     // Find in a <textarea> content.
     EXPECT_TRUE(frame->find(findIdentifier, WebString::fromUTF8("bar3"), options, false, 0));
@@ -3611,7 +3611,7 @@ TEST_P(ParameterizedWebFrameTest, FindInPage)
     ASSERT_FALSE(range.isNull());
     EXPECT_EQ(5, range.startOffset());
     EXPECT_EQ(9, range.endOffset());
-    EXPECT_EQ(WebString::fromUTF8("TEXTAREA"), frame->document().focusedElement().tagName());
+    EXPECT_TRUE(frame->document().focusedElement().hasHTMLTagName("textarea"));
 
     // Find in a contentEditable element.
     EXPECT_TRUE(frame->find(findIdentifier, WebString::fromUTF8("bar4"), options, false, 0));
@@ -3622,7 +3622,7 @@ TEST_P(ParameterizedWebFrameTest, FindInPage)
     EXPECT_EQ(0, range.startOffset());
     EXPECT_EQ(4, range.endOffset());
     // "bar4" is surrounded by <span>, but the focusable node should be the parent <div>.
-    EXPECT_EQ(WebString::fromUTF8("DIV"), frame->document().focusedElement().tagName());
+    EXPECT_TRUE(frame->document().focusedElement().hasHTMLTagName("div"));
 
     // Find in <select> content.
     EXPECT_FALSE(frame->find(findIdentifier, WebString::fromUTF8("bar5"), options, false, 0));