Mac: Fix Korean input on OSX 10.11

content/browser/renderer_host/render_widget_host_view_mac.mm

Index: content/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index b060993bc86b60f4deef82fbd628feecf78464c1..7144d9a80315c1470773f41e6b558b30e44d28e4 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -2101,6 +2101,7 @@ void RenderWidgetHostViewMac::OnDisplayMetricsChanged(
   // Clear them here so that we can know whether they have changed afterwards.
   textToBeInserted_.clear();
   markedText_.clear();
+  markedTextSelectedRange_ = NSMakeRange(NSNotFound, 0);
   underlines_.clear();
   unmarkTextCalled_ = NO;
   hasEditCommands_ = NO;
@@ -2184,11 +2185,11 @@ void RenderWidgetHostViewMac::OnDisplayMetricsChanged(
   if (hasMarkedText_ && markedText_.length()) {
     // Sends the updated marked text to the renderer so it can update the
     // composition node in WebKit.
-    // When marked text is available, |selectedRange_| will be the range being
-    // selected inside the marked text.
+    // When marked text is available, |markedTextSelectedRange_| will be the
+    // range being selected inside the marked text.
     widgetHost->ImeSetComposition(markedText_, underlines_,
-                                  selectedRange_.location,
-                                  NSMaxRange(selectedRange_));
+                                  markedTextSelectedRange_.location,
+                                  NSMaxRange(markedTextSelectedRange_));
   } else if (oldHasMarkedText && !hasMarkedText_ && !textInserted) {
     if (unmarkTextCalled_) {
       widgetHost->ImeConfirmComposition(
@@ -2863,6 +2864,13 @@ extern NSString *NSTextInputReplacementRangeAttributeName;
   return rect;
 }
 
+- (NSRange)selectedRange {
+  if (hasMarkedText_)
+    return NSMakeRange(NSMaxRange(markedRange_), 0);

[James Su, 2015/07/17 03:47:37]

I'm not sure if this logic is necessary. The developer document:
https://developer.apple.com/library/mac/documentation/Cocoa/Reference/NSTextI...
doesn't mention this behavior.

Can you remove this whole method and test the behavior?

[Andre, 2015/07/17 18:05:44]

Thanks James.
This is actually the main fix for the bug.
AppKit calls this then calls -attributedSubstringForProposedRange:actualRange:
based on the returned value.
It ends up asking for the wrong substring for working with the current
composition because selectedRange is
wrong.
The selection caret is placed after the marked text, so selectedRange should
point the end of the text,
but the selectedRange we get from blink does not include the marked text for
some reason.
For example, if we have 2 commited characters and 1 character marked text,
selectedRange should be (3, 0)
but we were returning (2,0).

[James Su, 2015/07/18 02:26:33]

Can you investigate the root cause of this issue? I'd prefer to fix the root
cause rather than workaround the issue here.

+
+  return selectedRange_;
+}
+
 - (NSRange)markedRange {
   // An input method calls this method to check if an application really has
   // a text being composed when hasMarkedText call returns true.
@@ -2922,6 +2930,7 @@ extern NSString *NSTextInputReplacementRangeAttributeName;
   // input method calls this method.
   hasMarkedText_ = NO;
   markedText_.clear();
+  markedTextSelectedRange_ = NSMakeRange(NSNotFound, 0);
   underlines_.clear();
 
   // If we are handling a key down event, then ConfirmComposition() will be
@@ -2946,7 +2955,7 @@ extern NSString *NSTextInputReplacementRangeAttributeName;
   int length = [im_text length];
 
   // |markedRange_| will get set on a callback from ImeSetComposition().
-  selectedRange_ = newSelRange;
+  markedTextSelectedRange_ = newSelRange;
   markedText_ = base::SysNSStringToUTF16(im_text);
   hasMarkedText_ = (length > 0);