Add supports that allow Autofill to be initiated from textarea field

components/autofill/content/renderer/form_autofill_util.cc

Index: components/autofill/content/renderer/form_autofill_util.cc
diff --git a/components/autofill/content/renderer/form_autofill_util.cc b/components/autofill/content/renderer/form_autofill_util.cc
index 0657f78a4f64bdd7ba7056470281269ed797bb4a..123e929a211697d3245ed01e935a5c0cc935b5c9 100644
--- a/components/autofill/content/renderer/form_autofill_util.cc
+++ b/components/autofill/content/renderer/form_autofill_util.cc
@@ -438,6 +438,34 @@ base::string16 InferLabelForElement(const WebFormControlElement& element) {
   return InferLabelFromDivTable(element);
 }
 
+void HandleInitiatingNode(WebFormControlElement& element, bool preview) {

[Ilya Sherman, 2014/02/22 06:24:20]

nit: Pass-by-reference is almost entirely disallowed by the Chromium style
guide.  In this case, I'd recommend either pass-by-copy or pass-by-pointer.

+  WebInputElement* input_element = toWebInputElement(&element);
+  if (!IsTextInput(input_element) &&
+      !IsMonthInput(input_element) &&
+      !IsTextAreaElement(element))
+    return;
+
+  if (IsTextInput(input_element) || IsMonthInput(input_element)) {
+    if (preview) {
+      input_element->setSelectionRange(
+          input_element->value().length(),
+          input_element->suggestedValue().length());
+    } else {
+      input_element->setSelectionRange(input_element->value().length(),
+                                       input_element->value().length());
+    }
+  } else if (IsTextAreaElement(element)) {
+    WebTextAreaElement text_area = element.toConst<WebTextAreaElement>();
+    if (preview) {
+      text_area.setSelectionRange(text_area.value().length(),
+                                  text_area.suggestedValue().length());
+    } else {
+      text_area.setSelectionRange(text_area.value().length(),
+                                  text_area.value().length());
+    }
+  }
+}

[Ilya Sherman, 2014/02/22 06:24:20]

This method still makes it hard to tell that the code is doing the same thing
for both input elements and textarea elements.  Please decompose methods along
the lines of

WebString GetValue(const WebFormControlElement& element);
WebString GetSuggestedValue(const WebFormControlElement& element);
void SetSelectionRange(WebFormControlElement element, int start, int end);

+
 // Fills |option_strings| with the values of the <option> elements present in
 // |select_element|.
 void GetOptionStringsFromElement(const WebSelectElement& select_element,
@@ -540,8 +568,7 @@ void FillFormField(const FormFieldData& data,
     input_element->setValue(
         data.value.substr(0, input_element->maxLength()), true);
     if (is_initiating_node) {
-      int length = input_element->value().length();
-      input_element->setSelectionRange(length, length);
+      HandleInitiatingNode(*input_element, false);
       // Clear the current IME composition (the underline), if there is one.
       input_element->document().frame()->unmarkText();
     }
@@ -550,6 +577,11 @@ void FillFormField(const FormFieldData& data,
     if (text_area.value() != data.value) {
       text_area.setValue(data.value);
       text_area.dispatchFormControlChangeEvent();
+      if (is_initiating_node) {
+        HandleInitiatingNode(text_area, false);
+        // Clear the current IME composition (the underline), if there is one.
+        text_area.document().frame()->unmarkText();
+      }
     }
   } else if (IsSelectElement(*field)) {
     WebSelectElement select_element = field->to<WebSelectElement>();
@@ -582,16 +614,17 @@ void PreviewFormField(const FormFieldData& data,
     input_element->setSuggestedValue(
       data.value.substr(0, input_element->maxLength()));
     input_element->setAutofilled(true);
-    if (is_initiating_node) {
+    if (is_initiating_node)

[Ilya Sherman, 2014/02/22 06:24:20]

nit: Curly braces are still needed, since the body of the loop spans two lines
of text.

       // Select the part of the text that the user didn't type.
-      input_element->setSelectionRange(
-          input_element->value().length(),
-          input_element->suggestedValue().length());
-    }
+      HandleInitiatingNode(*input_element, true);
+
   } else if (IsTextAreaElement(*field)) {
     WebTextAreaElement textarea = field->to<WebTextAreaElement>();
     textarea.setSuggestedValue(data.value);
     field->setAutofilled(true);
+    if (is_initiating_node)

[Ilya Sherman, 2014/02/22 06:24:20]

nit: Curly braces are still needed, since the body of the loop spans two lines
of text.

+      // Select the part of the text that the user didn't type.
+      HandleInitiatingNode(textarea, true);
   }
 }
 
@@ -784,7 +817,13 @@ void WebFormControlElementToFormField(const WebFormControlElement& element,
     field->text_direction = input_element->directionForFormData() == "rtl" ?
         base::i18n::RIGHT_TO_LEFT : base::i18n::LEFT_TO_RIGHT;
   } else if (IsTextAreaElement(element)) {
-    // Nothing more to do in this case.
+    const WebTextAreaElement textarea_element =
+        element.toConst<WebTextAreaElement>();
+    field->is_autofilled = element.isAutofilled();
+    field->is_focusable = element.isFocusable();
+    field->should_autocomplete = textarea_element.autoComplete();
+    field->text_direction = textarea_element.directionForFormData() == "rtl" ?
+        base::i18n::RIGHT_TO_LEFT : base::i18n::LEFT_TO_RIGHT;

[Ilya Sherman, 2014/02/22 06:24:20]

Is it possible to refactor the code so that it is shared across the two branches
of the if/else, rather than duplicated?

   } else if (extract_mask & EXTRACT_OPTIONS) {
     // Set option strings on the field if available.
     DCHECK(IsSelectElement(element));
@@ -971,10 +1010,10 @@ bool WebFormElementToFormData(
   return true;
 }
 
-bool FindFormAndFieldForInputElement(const WebInputElement& element,
-                                     FormData* form,
-                                     FormFieldData* field,
-                                     RequirementsMask requirements) {
+bool FindFormAndFieldForFormControlElement(const WebFormControlElement& element,
+                                           FormData* form,
+                                           FormFieldData* field,
+                                           RequirementsMask requirements) {
   if (!IsAutofillableElement(element))
     return false;
 
@@ -992,7 +1031,7 @@ bool FindFormAndFieldForInputElement(const WebInputElement& element,
                                   field);
 }
 
-void FillForm(const FormData& form, const WebInputElement& element) {
+void FillForm(const FormData& form, const WebFormControlElement& element) {
   WebFormElement form_element = element.form();
   if (form_element.isNull())
     return;
@@ -1033,7 +1072,7 @@ void FillFormForAllElements(const FormData& form_data,
                            &FillFormField);
 }
 
-void PreviewForm(const FormData& form, const WebInputElement& element) {
+void PreviewForm(const FormData& form, const WebFormControlElement& element) {
   WebFormElement form_element = element.form();
   if (form_element.isNull())
     return;
@@ -1046,7 +1085,7 @@ void PreviewForm(const FormData& form, const WebInputElement& element) {
                            &PreviewFormField);
 }
 
-bool ClearPreviewedFormWithElement(const WebInputElement& element,
+bool ClearPreviewedFormWithElement(const WebFormControlElement& element,
                                    bool was_autofilled) {
   WebFormElement form_element = element.form();
   if (form_element.isNull())
@@ -1083,26 +1122,27 @@ bool ClearPreviewedFormWithElement(const WebInputElement& element,
     if (IsTextInput(input_element)) {
       input_element->setSuggestedValue(WebString());
       bool is_initiating_node = (element == *input_element);
-      if (is_initiating_node)
+      if (is_initiating_node) {
         input_element->setAutofilled(was_autofilled);
-      else
+        // Clearing the suggested value in the focused node (above) can cause
+        // selection to be lost. We force selection range to restore the text
+        // cursor.
+        HandleInitiatingNode(*input_element, false);

[Ilya Sherman, 2014/02/22 06:24:20]

This change doesn't seem appropriate.  Is there some specific bug that this is
meant to be addressing?

+      }
+      else {

[Ilya Sherman, 2014/02/22 06:24:20]

nit: The else should be on the previous line, i.e. "} else {"

         input_element->setAutofilled(false);
-
-      // Clearing the suggested value in the focused node (above) can cause
-      // selection to be lost. We force selection range to restore the text
-      // cursor.
-      if (is_initiating_node) {
-        int length = input_element->value().length();
-        input_element->setSelectionRange(length, length);
       }
     } else if (IsTextAreaElement(control_element)) {
       WebTextAreaElement text_area = control_element.to<WebTextAreaElement>();
       text_area.setSuggestedValue(WebString());
       bool is_initiating_node = (element == text_area);
-      if (is_initiating_node)
+      if (is_initiating_node) {
         control_element.setAutofilled(was_autofilled);
-      else
+        HandleInitiatingNode(text_area, false);
+      }
+      else {
         control_element.setAutofilled(false);
+      }
     }
   }
 
@@ -1179,7 +1219,7 @@ bool IsWebElementEmpty(const blink::WebElement& element) {
   return true;
 }
 
-gfx::RectF GetScaledBoundingBox(float scale, WebInputElement* element) {
+gfx::RectF GetScaledBoundingBox(float scale, WebFormControlElement* element) {
   gfx::Rect bounding_box(element->boundsInViewportSpace());
   return gfx::RectF(bounding_box.x() * scale,
                     bounding_box.y() * scale,