Add missing .h files to .gn files that have a .cc file next to it in the gn file already.

third_party/WebKit/Source/core/html/BUILD.gn

Index: third_party/WebKit/Source/core/html/BUILD.gn
diff --git a/third_party/WebKit/Source/core/html/BUILD.gn b/third_party/WebKit/Source/core/html/BUILD.gn
index f605c3de975ca459184063b6bc5a3f48cfb9c213..65c6ae5b1f32d9646d97c9b37af5156c6f880229 100644
--- a/third_party/WebKit/Source/core/html/BUILD.gn
+++ b/third_party/WebKit/Source/core/html/BUILD.gn
@@ -40,6 +40,7 @@ blink_core_sources("html") {
     "HTMLCanvasElement.cpp",
     "HTMLCanvasElement.h",
     "HTMLCollection.cpp",
+    "HTMLCollection.h",
     "HTMLContentElement.cpp",
     "HTMLContentElement.h",
     "HTMLDListElement.cpp",
@@ -57,7 +58,9 @@ blink_core_sources("html") {
     "HTMLDivElement.cpp",
     "HTMLDivElement.h",
     "HTMLDocument.cpp",
+    "HTMLDocument.h",
     "HTMLElement.cpp",
+    "HTMLElement.h",
     "HTMLEmbedElement.cpp",
     "HTMLEmbedElement.h",
     "HTMLFieldSetElement.cpp",
@@ -65,13 +68,19 @@ blink_core_sources("html") {
     "HTMLFontElement.cpp",
     "HTMLFontElement.h",
     "HTMLFormControlElement.cpp",
+    "HTMLFormControlElement.h",
     "HTMLFormControlElementWithState.cpp",
+    "HTMLFormControlElementWithState.h",
     "HTMLFormControlsCollection.cpp",
     "HTMLFormControlsCollection.h",
     "HTMLFormElement.cpp",
+    "HTMLFormElement.h",
     "HTMLFrameElement.cpp",
+    "HTMLFrameElement.h",
     "HTMLFrameElementBase.cpp",
+    "HTMLFrameElementBase.h",
     "HTMLFrameOwnerElement.cpp",
+    "HTMLFrameOwnerElement.h",
     "HTMLFrameSetElement.cpp",
     "HTMLFrameSetElement.h",
     "HTMLHRElement.cpp",
@@ -83,6 +92,7 @@ blink_core_sources("html") {
     "HTMLHtmlElement.cpp",
     "HTMLHtmlElement.h",
     "HTMLIFrameElement.cpp",
+    "HTMLIFrameElement.h",
     "HTMLIFrameElementAllow.cpp",
     "HTMLIFrameElementAllow.h",
     "HTMLIFrameElementSandbox.cpp",
@@ -94,6 +104,7 @@ blink_core_sources("html") {
     "HTMLImageLoader.cpp",
     "HTMLImageLoader.h",
     "HTMLInputElement.cpp",
+    "HTMLInputElement.h",
     "HTMLLIElement.cpp",
     "HTMLLIElement.h",
     "HTMLLabelElement.cpp",
@@ -107,6 +118,7 @@ blink_core_sources("html") {
     "HTMLMarqueeElement.cpp",
     "HTMLMarqueeElement.h",
     "HTMLMediaElement.cpp",
+    "HTMLMediaElement.h",
     "HTMLMediaElementControlsList.cpp",
     "HTMLMediaElementControlsList.h",
     "HTMLMediaSource.cpp",
@@ -144,6 +156,7 @@ blink_core_sources("html") {
     "HTMLParamElement.cpp",
     "HTMLParamElement.h",
     "HTMLPictureElement.cpp",
+    "HTMLPictureElement.h",
     "HTMLPlugInElement.cpp",
     "HTMLPlugInElement.h",
     "HTMLPreElement.cpp",
@@ -175,11 +188,13 @@ blink_core_sources("html") {
     "HTMLTableCaptionElement.cpp",
     "HTMLTableCaptionElement.h",
     "HTMLTableCellElement.cpp",
+    "HTMLTableCellElement.h",
     "HTMLTableColElement.cpp",
     "HTMLTableColElement.h",
     "HTMLTableElement.cpp",
     "HTMLTableElement.h",
     "HTMLTablePartElement.cpp",
+    "HTMLTablePartElement.h",
     "HTMLTableRowElement.cpp",
     "HTMLTableRowElement.h",
     "HTMLTableRowsCollection.cpp",
@@ -191,6 +206,7 @@ blink_core_sources("html") {
     "HTMLTemplateElement.cpp",
     "HTMLTemplateElement.h",
     "HTMLTextAreaElement.cpp",
+    "HTMLTextAreaElement.h",
     "HTMLTitleElement.cpp",
     "HTMLTitleElement.h",
     "HTMLTrackElement.cpp",
@@ -210,6 +226,7 @@ blink_core_sources("html") {
     "ImageDocument.cpp",
     "ImageDocument.h",
     "LabelableElement.cpp",
+    "LabelableElement.h",
     "LabelsNodeList.cpp",
     "LabelsNodeList.h",
     "LinkManifest.cpp",
@@ -386,6 +403,7 @@ blink_core_sources("html") {
     "parser/HTMLMetaCharsetParser.cpp",
     "parser/HTMLMetaCharsetParser.h",
     "parser/HTMLParserIdioms.cpp",
+    "parser/HTMLParserIdioms.h",
     "parser/HTMLParserOptions.cpp",
     "parser/HTMLParserOptions.h",
     "parser/HTMLParserReentryPermit.cpp",
@@ -417,6 +435,7 @@ blink_core_sources("html") {
     "parser/MarkupTokenizerInlines.h",
     "parser/NestingLevelIncrementer.h",
     "parser/PreloadRequest.cpp",
+    "parser/PreloadRequest.h",
     "parser/ResourcePreloader.cpp",
     "parser/TextDocumentParser.cpp",
     "parser/TextDocumentParser.h",
@@ -487,6 +506,7 @@ blink_core_sources("html") {
     "track/TextTrackCueList.cpp",
     "track/TextTrackCueList.h",
     "track/TextTrackList.cpp",
+    "track/TextTrackList.h",
     "track/TrackBase.cpp",
     "track/TrackBase.h",
     "track/TrackEvent.cpp",