Include git hash in debuglog.

app/build.gradle

@@ -108,6 +108,7 @@ android {
         project.ext.set("archivesBaseName", "Signal");
 
         buildConfigField "long", "BUILD_TIMESTAMP", getLastCommitTimestamp() + "L"
+        buildConfigField "String", "GIT_HASH", "\"${getGitHash()}\""
         buildConfigField "String", "SIGNAL_URL", "\"https://textsecure-service.whispersystems.org\""
         buildConfigField "String", "STORAGE_URL", "\"https://storage.signal.org\""
         buildConfigField "String", "SIGNAL_CDN_URL", "\"https://cdn.signal.org\""
@@ -486,6 +487,15 @@ def getLastCommitTimestamp() {
     }
 }
 
+def getGitHash() {
+    def stdout = new ByteArrayOutputStream()
+    exec {
+        commandLine 'git', 'rev-parse', '--short', 'HEAD'
+        standardOutput = stdout
+    }
+    return stdout.toString().trim()
+}
+
 tasks.withType(Test) {
     testLogging {
         events "failed"

app/src/main/java/org/thoughtcrime/securesms/logsubmit/LogSectionSystemInfo.java

@@ -73,7 +73,8 @@ public class LogSectionSystemInfo implements LogSection {
              .append(BuildConfig.CANONICAL_VERSION_CODE)
              .append(", ")
              .append(Util.getManifestApkVersion(context))
-             .append(")\n");
+             .append(") (")
+             .append(BuildConfig.GIT_HASH).append(") \n");
     } catch (PackageManager.NameNotFoundException nnfe) {
       builder.append("Unknown\n");
     }