[Autofill/Autocomplete Feature] Substring matching instead of prefix matching.

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 51a2251258b73d0faf6bf61afbc8fec36b951d11..21810ec71be7c18debad93d6b5a9e3c185ccecbc 100644
--- a/components/autofill/content/renderer/form_autofill_util.cc
+++ b/components/autofill/content/renderer/form_autofill_util.cc
@@ -16,6 +16,7 @@
 #include "components/autofill/core/common/autofill_data_validation.h"
 #include "components/autofill/core/common/autofill_regexes.h"
 #include "components/autofill/core/common/autofill_switches.h"
+#include "components/autofill/core/common/autofill_util.h"
 #include "components/autofill/core/common/form_data.h"
 #include "components/autofill/core/common/form_field_data.h"
 #include "third_party/WebKit/public/platform/WebString.h"
@@ -871,9 +872,7 @@ void PreviewFormField(const FormFieldData& data,
   if (is_initiating_node &&
       (IsTextInput(input_element) || IsTextAreaElement(*field))) {
     // Select the part of the text that the user didn't type.
-    int start = field->value().length();
-    int end = field->suggestedValue().length();
-    field->setSelectionRange(start, end);
+    PreviewSuggestion(field, data.value, field->value());

[please use gerrit instead, 2015/06/30 19:06:23]

Pass in input_element->suggestedValue() instead of data.value, because the
former is truncated.

[Pritam Nikam, 2015/07/01 17:25:59]

Done.

   }
 }
 
@@ -1534,4 +1533,14 @@ gfx::RectF GetScaledBoundingBox(float scale, WebElement* element) {
                     bounding_box.height() * scale);
 }
 
+void PreviewSuggestion(WebFormControlElement* input_element,
+                       const base::string16& suggestion,
+                       const base::string16& user_input) {
+  input_element->setSelectionRange(
+      IsFeatureSubstringMatchEnabled()
+          ? autofill::GetTextSelectionStart(suggestion, user_input)
+          : user_input.size(),
+      suggestion.size());

[please use gerrit instead, 2015/06/30 19:06:23]

Lines 1542-1543: We usually use length() for strings and size() for vectors.
Let's use length() here.

[Pritam Nikam, 2015/07/01 17:25:59]

Done.

+}
+
 }  // namespace autofill