ime: Add flag for latin-based physical typing using shared library.

Add a new feature flag, that when enabled, uses the IME shared library
for physical typing in languages based on latin script.

Bug: 1019541
Change-Id: Ib3a84fe19028164c82947f4257c2787005cb4b2b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2371064
Commit-Queue: Darren Shen <shend@chromium.org>
Reviewed-by: Keith Lee <keithlee@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804017}

chrome/browser/extensions/api/virtual_keyboard_private/chrome_virtual_keyboard_delegate.cc

@@ -417,6 +417,10 @@ void ChromeVirtualKeyboardDelegate::OnHasInputDevices(
   features->AppendString(GenerateFeatureFlag(
       "assistiveAutoCorrect",
       base::FeatureList::IsEnabled(chromeos::features::kAssistAutoCorrect)));
+  features->AppendString(
+      GenerateFeatureFlag("systemlatinphysicaltyping",
+                          base::FeatureList::IsEnabled(
+                              chromeos::features::kSystemLatinPhysicalTyping)));
 
   results->Set("features", std::move(features));
 

chromeos/constants/chromeos_features.cc

@@ -480,6 +480,11 @@ const base::Feature kSplitSettingsSync{"SplitSettingsSync",
 const base::Feature kSuggestedContentToggle{"SuggestedContentToggle",
                                             base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Enables or disables using the system input engine for physical typing in
+// languages based on latin script.
+const base::Feature kSystemLatinPhysicalTyping{
+    "SystemLatinPhysicalTyping", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Enables Chrome OS Telemetry Extension.
 const base::Feature kTelemetryExtension{"TelemetryExtension",
                                         base::FEATURE_DISABLED_BY_DEFAULT};

chromeos/constants/chromeos_features.h

@@ -207,6 +207,8 @@ extern const base::Feature kSplitSettingsSync;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kSuggestedContentToggle;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
+extern const base::Feature kSystemLatinPhysicalTyping;
+COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kTelemetryExtension;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kUnifiedMediaView;