File constructor understands lastModified.

LayoutTests/fast/files/file-constructor-expected.txt

Index: LayoutTests/fast/files/file-constructor-expected.txt
diff --git a/LayoutTests/fast/files/file-constructor-expected.txt b/LayoutTests/fast/files/file-constructor-expected.txt
index 2c4bf484e46e3d13203a87b33ee2ad91bf1b1031..728cd0e5a781d981ad245581d5680035e8212aba 100644
--- a/LayoutTests/fast/files/file-constructor-expected.txt
+++ b/LayoutTests/fast/files/file-constructor-expected.txt
@@ -45,6 +45,9 @@ PASS new File([], 'world.html', {endings:'illegalValue'}) threw exception TypeEr
 PASS new File([], 'world.html', {endings:throwingObj}) threw exception Error.
 PASS new File([], 'world.html', {type:throwingObj}) threw exception Error.
 PASS new File([], 'world.html', {type:'helloî'}) threw exception SyntaxError: Failed to construct 'File': The "type" property must consist of ASCII characters..
+PASS new File([], 'world.html', {lastModifiedDate: 'not a date'}) threw exception TypeError: Failed to construct 'File': The "lastModifiedDate" property must be a Date instance..
+PASS new File([], 'world.html', {lastModifiedDate: null}) threw exception TypeError: Failed to construct 'File': The "lastModifiedDate" property must be a Date instance..
+PASS new File([], 'world.html', {lastModifiedDate: Date.now()}) threw exception TypeError: Failed to construct 'File': The "lastModifiedDate" property must be a Date instance..
 PASS (new File([], 'world.html', null)) instanceof window.File threw exception TypeError: Failed to construct 'File': The 3rd argument is not of type Object..
 PASS (new File([], 'world.html', undefined)) instanceof window.File threw exception TypeError: Failed to construct 'File': The 3rd argument is not of type Object..
 PASS (new File([], 'world.html', 123)) instanceof window.File threw exception TypeError: Failed to construct 'File': The 3rd argument is not of type Object..
@@ -58,6 +61,13 @@ PASS (new File([], 'world.html', {type:'text/html'})).name is 'world.html'
 PASS (new File([], 'world.html', {type:'text/html'})).type is 'text/html'
 PASS (new File([], 'world.html', {type:'text/html'})).size is 0
 PASS (new File([], 'world.html', {type:'text/plain;charset=UTF-8'})).type is 'text/plain;charset=utf-8'
+PASS (new File([], 'world.html', {lastModifiedDate: aDate})).lastModifiedDate instanceof Date is true
+PASS (new File([], 'world.html', {lastModifiedDate: aDate})).lastModifiedDate.valueOf() is aDate.valueOf()
+PASS (new File([], 'world.html', {lastModifiedDate: new Date(NaN)})).lastModifiedDate instanceof Date is true
+PASS (new File([], 'world.html', {lastModifiedDate: new Date(NaN)})).lastModifiedDate.valueOf() is NaN
+PASS (new File([], 'world.html')).lastModifiedDate instanceof Date is true
+PASS startTime <= fileTime is true
+PASS fileTime <= endTime is true
 PASS window.File.length is 2
 PASS new File([new DataView(new ArrayBuffer(100))], 'world.html').size is 100
 PASS new File([new Uint8Array(100)], 'world.html').size is 100