Fix PHP non-conformance when parsing JSON booleans into float/double fields.

In https://github.com/protocolbuffers/protobuf/commit/cb440834fde94f4fa2433fdb71b6366d7b1713a9 we discovered an issue where boolean inputs can be
parsed into float fields in PHP due to a missing is_numeric check.
(Note that this is_numeric check is present for int fields).

This is very unintended, and this is a behavioral fix.

PiperOrigin-RevId: 952923362

conformance/failure_list_php.txt

diff --git a/conformance/failure_list_php.txt b/conformance/failure_list_php.txt
index 6e54a83..c9a32d8 100644
--- a/conformance/failure_list_php.txt
+++ b/conformance/failure_list_php.txt
@@ -47,12 +47,8 @@
 Required.*.DurationProtoNanosWrongSignNegativeSecs.JsonOutput # Should have failed to serialize, but didn't.
 Required.*.TimestampProtoNanoTooLarge.JsonOutput # Should have failed to serialize, but didn't.
 Required.*.TimestampProtoNegativeNanos.JsonOutput # Should have failed to serialize, but didn't.
-Required.*.JsonInput.SingleValueForRepeatedFieldInt32 # Should have failed to parse, but didn't.
+Required.*.JsonInput.SingleValueForRepeatedFieldInt32                                                              # Should have failed to parse, but didn't.
 Required.*.ProtobufInput.BadTag_FieldNumberTooHigh                                                                 # Should have failed to parse, but didn't.
 Required.*.ProtobufInput.BadTag_FieldNumberSlightlyTooHigh                                                         # Should have failed to parse, but didn't.
 Required.*.ProtobufInput.BadTag_OverlongVarint                                                                     # Should have failed to parse, but didn't.
 Required.*.ProtobufInput.BadTag_VarintMoreThanTenBytes                                                             # Should have failed to parse, but didn't.
-Required.*.JsonInput.DoubleFieldFalseValue                                                                         # Should have failed to parse, but didn't.
-Required.*.JsonInput.DoubleFieldTrueValue                                                                          # Should have failed to parse, but didn't.
-Required.*.JsonInput.FloatFieldFalseValue                                                                          # Should have failed to parse, but didn't.
-Required.*.JsonInput.FloatFieldTrueValue                                                                           # Should have failed to parse, but didn't.

php/src/Google/Protobuf/Internal/Message.php

diff --git a/php/src/Google/Protobuf/Internal/Message.php b/php/src/Google/Protobuf/Internal/Message.php
index 892456d..b4ec5ea 100644
--- a/php/src/Google/Protobuf/Internal/Message.php
+++ b/php/src/Google/Protobuf/Internal/Message.php
@@ -932,6 +932,10 @@
                 if ($value === "NaN") {
                     return NAN;
                 }
+                if (!is_numeric($value)) {
+                   throw new GPBDecodeException(
+                       "Invalid data type for float field");
+                }
                 return $value;
             case GPBType::INT32:
             case GPBType::SINT32: