Make TabLayout text color finchable.

Our PM wants to make the font color of the non-selected language
finch-able to figure out a path forward with making the font darker.
Group 1 will be the default color and group 2 will be the 87% black.

I created the params with our feature TranslateCompactUI and tested by
'--force-fieldtrials=TranslateCompactUI/Enabled --force-fieldtrial-params
=TranslateCompactUI.Enabled:translate_tab_default_text_color/1'

Bug: 771835
Change-Id: I0d2d4eea3707685b45b83e5d7d4079fa855deecd
Reviewed-on: https://chromium-review.googlesource.com/701994Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Leo Zhang <googleo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#506956}

chrome/android/java/src/org/chromium/chrome/browser/infobar/TranslateCompactInfoBar.java

@@ -5,6 +5,7 @@
 package org.chromium.chrome.browser.infobar;
 
 import android.support.design.widget.TabLayout;
+import android.support.v4.content.ContextCompat;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.OnClickListener;
@@ -42,6 +43,7 @@ public class TranslateCompactInfoBar extends InfoBar
     public static final int ACTION_AUTO_NEVER_LANGUAGE = 4;
 
     private final int mInitialStep;
+    private final int mDefaultTextColor;
     private final TranslateOptions mOptions;
 
     private long mNativeTranslateInfoBarPtr;
@@ -157,18 +159,20 @@ public class TranslateCompactInfoBar extends InfoBar
     @CalledByNative
     private static InfoBar create(int initialStep, String sourceLanguageCode,
             String targetLanguageCode, boolean alwaysTranslate, boolean triggeredFromMenu,
-            String[] languages, String[] languageCodes, int[] hashCodes) {
+            String[] languages, String[] languageCodes, int[] hashCodes, int tabTextColor) {
         recordInfobarAction(INFOBAR_IMPRESSION);
         return new TranslateCompactInfoBar(initialStep, sourceLanguageCode, targetLanguageCode,
-                alwaysTranslate, triggeredFromMenu, languages, languageCodes, hashCodes);
+                alwaysTranslate, triggeredFromMenu, languages, languageCodes, hashCodes,
+                tabTextColor);
     }
 
     TranslateCompactInfoBar(int initialStep, String sourceLanguageCode, String targetLanguageCode,
             boolean alwaysTranslate, boolean triggeredFromMenu, String[] languages,
-            String[] languageCodes, int[] hashCodes) {
+            String[] languageCodes, int[] hashCodes, int tabTextColor) {
         super(R.drawable.infobar_translate_compact, null, null);
 
         mInitialStep = initialStep;
+        mDefaultTextColor = tabTextColor;
         mOptions = TranslateOptions.create(sourceLanguageCode, targetLanguageCode, languages,
                 languageCodes, alwaysTranslate, triggeredFromMenu, hashCodes);
     }
@@ -196,6 +200,11 @@ public class TranslateCompactInfoBar extends InfoBar
         });
 
         mTabLayout = (TranslateTabLayout) content.findViewById(R.id.translate_infobar_tabs);
+        if (mDefaultTextColor > 0) {
+            mTabLayout.setTabTextColors(
+                    ContextCompat.getColor(getContext(), R.color.black_alpha_87),
+                    ContextCompat.getColor(getContext(), R.color.infobar_accent_blue));
+        }
         mTabLayout.addTabs(mOptions.sourceLanguageName(), mOptions.targetLanguageName());
 
         // Set translating status in the beginning for pages translated automatically.

chrome/browser/ui/android/infobars/translate_compact_infobar.cc

@@ -33,6 +33,7 @@ const char kTranslateMaxNumberOfAutoAlways[] =
     "translate_max_number_of_auto_always";
 const char kTranslateMaxNumberOfAutoNever[] =
     "translate_max_number_of_auto_never";
+const char kTranslateTabDefaultTextColor[] = "translate_tab_default_text_color";
 
 // TranslateInfoBar -----------------------------------------------------------
 
@@ -72,7 +73,7 @@ ScopedJavaLocalRef<jobject> TranslateCompactInfoBar::CreateRenderInfoBar(
       env, delegate->translate_step(), source_language_code,
       target_language_code, delegate->ShouldAlwaysTranslate(),
       delegate->triggered_from_menu(), java_languages, java_codes,
-      java_hash_codes);
+      java_hash_codes, TabDefaultTextColor());
 }
 
 void TranslateCompactInfoBar::ProcessButton(int action) {
@@ -229,6 +230,10 @@ int TranslateCompactInfoBar::MaxNumberOfAutoNever() {
   return GetParam(kTranslateMaxNumberOfAutoNever, kDefaultMaxNumberOfAutoNever);
 }
 
+int TranslateCompactInfoBar::TabDefaultTextColor() {
+  return GetParam(kTranslateTabDefaultTextColor, 0);
+}
+
 translate::TranslateInfoBarDelegate* TranslateCompactInfoBar::GetDelegate() {
   return delegate()->AsTranslateInfoBarDelegate();
 }

chrome/browser/ui/android/infobars/translate_compact_infobar.h

@@ -82,6 +82,10 @@ class TranslateCompactInfoBar
   // This is the maximum number of times to trigger "Never Translate"
   // automatically.
   int MaxNumberOfAutoNever();
+  // Get the value of the finch parameter: translate_tab_default_text_color.
+  // Default value is 0, which means using TabLayout default color.
+  // If it's not 0, we will set the text color manually based on the value.
+  int TabDefaultTextColor();
 
   translate::TranslateInfoBarDelegate* GetDelegate();