Complete Joda-Time to java.time migration (#3039)

This completes the exhaustive refactoring of foundational temporal types from Joda-Time to the native java.time API across the entire codebase.

- Replaced org.joda.time.DateTime, Instant, LocalDate, and Duration with java.time equivalents.
- Audited and updated Clock implementations (FakeClock, SystemClock). Added nowMillis(), nowDate(), and nowDateTime() to eliminate repetitive conversions and maintain parallel naming.
- Replaced ZonedDateTime with OffsetDateTime globally per go/avoid-zdt. OffsetDateTime is a better fit as we use a hardcoded ZoneOffset.UTC throughout the system, making geographical time zone rules (like daylight saving time) irrelevant and preventing serialization ambiguities. Added a presubmit check.
- Completely removed all transitional bridge methods from DateTimeUtils and deleted obsolete converters (e.g., DateTimeConverter).
- Updated testing infrastructure, Apache Beam pipelines, custom JCommander parameters, and networking modules to solely rely on java.time primitives.
- Retained the lone necessary org.joda.time.Instant usage in SafeBrowsingTransforms required by the Apache Beam API.
- Cleared Gradle lockfiles and removed the joda-time dependency entirely from the build configuration.

config/nom_build.py

@@ -409,4 +409,3 @@ if __name__ == '__main__':
         sys.exit(main(sys.argv))
     except Abort as ex:
         sys.exit(1)
-

config/presubmits.py

@@ -102,6 +102,22 @@ PRESUBMITS = {
                    {"node_modules/", ".idea"}, REQUIRED):
         "Source files must end in a newline.",
 
+    # Files must not end with extraneous blank lines
+    PresubmitCheck(
+        r".*\n\n$",
+        ("java", "js", "soy", "sql", "py", "sh", "gradle", "ts", "xml"),
+        {"node_modules/", ".idea", "nomulus.golden.sql"},
+    ):
+        "Source files must not end with extraneous blank lines.",
+
+    # Duplicate empty lines
+    PresubmitCheck(
+        r".*\n\n\n.*",
+        ("java", "js", "soy", "sh", "gradle", "ts", "xml"),
+        {"node_modules/", ".idea"},
+    ):
+        "Source files must not contain duplicate empty lines.",
+
     # System.(out|err).println should only appear in tools/ or load-testing/
     PresubmitCheck(
         r".*\bSystem\s*\.\s*(?:out|err)\s*\.\s*print.*", "java", {
@@ -160,7 +176,8 @@ PRESUBMITS = {
             "SelfSignedCaCertificate.java",
             "X509Utils.java",
             "TmchCertificateAuthority.java",
-            "DelegatedCredentials.java"
+            "DelegatedCredentials.java",
+            "SslInitializerTestUtils.java"
         },
     ):
         "Do not use java.util.Date. Use classes in java.time package instead.",
@@ -202,85 +219,24 @@ PRESUBMITS = {
         {},
     ):
         "Do not use .isEqualTo(Optional.of(...)). Use Truth's .hasValue(...) instead.",
-    # TODO: Remove the java.time migration presubmit checks below once the entire codebase has been migrated to java.time.
     PresubmitCheck(
-        r".*toDateTime\(\s*toInstant\(.*",
-        "java",
-        {"DateTimeUtilsTest.java"},
-    ):
-        "Do not double-wrap toDateTime(toInstant(...)).",
-    PresubmitCheck(
-        r".*toInstant\(\s*toDateTime\(.*",
-        "java",
-        {"DateTimeUtilsTest.java"},
-    ):
-        "Do not double-wrap toInstant(toDateTime(...)).",
-    PresubmitCheck(
-        r".*toInstant\([^;]*[cC]lock\.now\(\).*",
+        r".*java\.time\.ZonedDateTime.*",
         "java",
         {},
     ):
-        "Do not use toInstant(clock.now()). Use clock.now() instead.",
-    PresubmitCheck(
-        r".*toDateTime\([^;]*[cC]lock\.now\(\).*",
-        "java",
-        {},
-    ):
-        "Do not use toDateTime(clock.now()). Use clock.now() and Instant overloads instead.",
-    PresubmitCheck(
-        r".*toInstant\([^;]*tm\(\)\.getTxTime\(\).*",
-        "java",
-        {},
-    ):
-        "Do not use toInstant(tm().getTxTime()). Use tm().getTxTime() instead.",
-    PresubmitCheck(
-        r".*toDateTime\([^;]*tm\(\)\.getTxTime\(\).*",
-        "java",
-        {},
-    ):
-        "Do not use toDateTime(tm().getTxTime()). Use tm().getTxTime() and Instant overloads instead.",
-    PresubmitCheck(
-        r".*\(\s*Instant\s*\)\s*(?:this\.)?(?:fakeClock|clock)\.now\(\s*\).*",
-        "java",
-        {},
-    ):
-        "Do not unnecessarily cast clock.now() to Instant.",
-    PresubmitCheck(
-        r".*toDateTime\(\s*Instant\.now\(.*",
-        "java",
-        {},
-    ):
-        "Do not wrap Instant.now() in toDateTime. Use DateTime.now(UTC) directly.",
-    PresubmitCheck(
-        r".*toInstant\(\s*DateTime\.now\(.*",
-        "java",
-        {},
-    ):
-        "Do not wrap DateTime.now() in toInstant. Use Instant.now().truncatedTo(ChronoUnit.MILLIS) directly.",
-    PresubmitCheck(
-        r".*toDateTime\(\s*Instant\.parse\(.*",
-        "java",
-        {"DateTimeUtilsTest.java"},
-    ):
-        "Do not wrap Instant.parse in toDateTime. Use DateTime.parse directly.",
-    PresubmitCheck(
-        r".*toInstant\(\s*DateTime\.parse\(.*",
-        "java",
-        {"DateTimeUtilsTest.java"},
-    ):
-        "Do not wrap DateTime.parse in toInstant. Use Instant.parse directly.",
-    PresubmitCheck(
-        r".*cloneProjectedAtTime\(\s*toDateTime\(.*",
-        "java",
-        {},
-    ):
-        "Do not use cloneProjectedAtTime(toDateTime(...)). Use cloneProjectedAtTime(...) instead.",
+        "Do not use java.time.ZonedDateTime. Use java.time.OffsetDateTime per go/avoid-zdt.",
     PresubmitCheck(
         r".*ZoneId\.of\(\s*\"UTC\"\s*\).*",
         "java",
         {},
     ):
-        "Do not use ZoneId.of(\"UTC\"). Use java.time.ZoneOffset.UTC."
+        "Do not use ZoneId.of(\"UTC\"). Use java.time.ZoneOffset.UTC.",
+    PresubmitCheck(
+        r".*org\.joda\.time.*",
+        "java",
+        {"SafeBrowsingTransforms.java"},
+    ):
+        "Do not use Joda-Time. Use java.time instead.",
 }
 
 # Note that this regex only works for one kind of Flyway file.  If we want to