Pull time from git.

build.gradle

@@ -41,7 +41,7 @@ repositories {
 }
 
 def gitSha = 'git rev-parse --short HEAD'.execute([], project.rootDir).text.trim()
-def buildTime = new Date().format("yyyy-MM-dd'T'HH:mm:ss'Z'", TimeZone.getTimeZone("UTC"))
+def gitTimestamp = 'git log -n 1 --format=%at'.execute([], rootDir).text.trim()
 
 def isCi = "true".equals(System.getenv("CI"))
 def preDexEnabled = "true".equals(System.getProperty("pre-dex", "true"))
@@ -73,8 +73,8 @@ android {
 
     signingConfig signingConfigs.u2020
 
-    buildConfigField "String", "GIT_SHA", "\"${gitSha}\""
-    buildConfigField "String", "BUILD_TIME", "\"${buildTime}\""
+    buildConfigField 'String', 'GIT_SHA', "\"${gitSha}\""
+    buildConfigField 'long', 'GIT_TIMESTAMP', "${gitTimestamp}"
 
     testInstrumentationRunner "com.jakewharton.u2020.U2020TestRunner"
   }

src/internalDebug/java/com/jakewharton/u2020/ui/debug/DebugView.java

@@ -59,6 +59,7 @@
 import javax.inject.Named;
 import okhttp3.Cache;
 import okhttp3.OkHttpClient;
+import org.threeten.bp.Instant;
 import org.threeten.bp.ZoneId;
 import org.threeten.bp.format.DateTimeFormatter;
 import org.threeten.bp.temporal.TemporalAccessor;
@@ -67,7 +68,6 @@
 
 import static butterknife.ButterKnife.findById;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
-import static org.threeten.bp.format.DateTimeFormatter.ISO_INSTANT;
 
 public final class DebugView extends FrameLayout {
   private static final DateTimeFormatter DATE_DISPLAY_FORMAT =
@@ -400,7 +400,7 @@ private void setupBuildSection() {
     buildCodeView.setText(String.valueOf(BuildConfig.VERSION_CODE));
     buildShaView.setText(BuildConfig.GIT_SHA);
 
-    TemporalAccessor buildTime = ISO_INSTANT.parse(BuildConfig.BUILD_TIME);
+    TemporalAccessor buildTime = Instant.ofEpochSecond(BuildConfig.GIT_TIMESTAMP);
     buildDateView.setText(DATE_DISPLAY_FORMAT.format(buildTime));
   }